Here it is folks! I did my best to translate Megamix Ushi. I might have misunderstood some things and I left some text out but I think I was able to translate the most important parts. If I find some more time, I will probably try to translate some of the sakana doujinshi too.
It starts off with Shuichi thinking about their first time. It's been one week since then and he nervously wonders when they will do it again. Yuki steps in.
Yuki: Haah... I'm exhausted. I want to eat some cake. Shuichi: Ah...Oh! Are you done with your work, Yuki? Yuki: I'm not done but it's enough for today. Shuichi: Is... Is that so? Then... I guess we'll do it soon... Yuki: It? Oh, you mean sex? Shuichi: N-No!!! That was my inner voice that slipped out! Yuki: Oy, your phone is ringing.
Shuichi looks at his phone.
Shuichi: It's from my mom. They've arrived at their hotel. She says hi to you. Yuki: Okinawa was it? You should have gone with them. Shuichi: Huh? It's fine. I didn't feel like going. Yuki: Having a second "first night" with your boyfriend was more important, huh?
Shuichi looks flustered.
Yuki: Oh. You're not denying it. Shuichi: Shut up! "Second first night" isn't even correct japanese, you "expert"!! Yuki: Whatever. Hurry up and get into the bathtub.
Shuichi is in the bathtub.
Shuichi thinks: *sigh* What kind of flirting is this? Damn it. He looks so good but in the end he really is a guy... It'd be better if we just stopped this or if I got myself a girlfriend instead. I wonder if I could tell mom that I've turned out to be gay. What will I do about it in the future? ...The future... I'm so happy right now but maybe it's impossible to keep this up in the long run. But still... I... about this person... I really...
We switch over to the bedroom, where Yuki is sucking Shuichi's nipples.
Shuichi: Hey... how long will you do that to only my chest?
Shuichi takes a moment to enjoy it until he grabs Yuki's head.
Shuichi: That's... Stop doing that to my breast already, Yuki! Yuki: I guess you really are sensitive there. Shuichi: I... I'm not! Yuki: Would you be able to come by me just touching your breast? Shuichi: Stop...it already! Ngh! Jerk!
Yuki continues harrassing Shuichi's nipples, while groping his ass. Shuichi thinks: I don't really get this person... But he's already gotten me this far... Shuichi continues to think that even though he is ticklish, Yuki is making him feel something beyond that. He is impressed by Yuki's skills. Shuichi throws his head back he grabs the sheets. He is moaning loudly. In the next panel we see a close up of Yuki's face.
Yuki: That sure was a loud voice you made. Should I make your hips quiver again? By touching you here?
Shuichi is thinking: Damn it! He's got me figured out!
They are talking dirty I guess until Shuichi has enough. We see a panel where he is kind of crying while yelling at Yuki to stop teasing him and that they should have proper sex already. Yuki starts digging around in Shuichi's ass, making Shuichi throw his head back again. They talk dirty like always and Yuki finally enters Shuichi. Sorry, I don't really get everything they are saying and to be honest, I don't think they say anything important either way. They say stuff like: "I'm coming" or "You sure are full of energy". You get the idea. In the end Shuichi just lays there, his eyes covered by his bangs and his arm over his pillow behind his head.
Yuki: Oy. Shui...
He grabs Shuichi's face to look at him but Shuichi doesn't seem to respond.
Yuki: Again, huh? He sure is easy to loose.
Yuki smirks.
Yuki: Well, not that it's a bad thing.
Yuki keeps going. Not sure what they say or think here so let's skip to when they sit in the bathtub again.
Shuichi: Hey, it doesn't bother you that I'm just like a kid, right? I mean, I'm enjoying this but...
Yuki: Hn? Not really. You're my lover so wouldn't it be weird if I thought like that?
Shuichi thinks: Somehow those words make me really happy...
Shuichi: Is... that so? That's good, then...
Yuki starts grabbing Shuichi again.
Shuichi: Are you serious? Yuki: It's fun~ Shuichi: Pervert! Damn homo! Die, you nipple man!
Shuichi secretly thinks: To be honest, I'm kind of starting to get in the mood again.
Yuki: You're starting to get in the mood, aren't you?
In the next panel Yuki is already pulling out of Shuichi.
Yuki: Who did you say is a damn homo? Shuichi: I...I am~ <3
Shuichi is thinking something about how they continued having sex countless times.
The next scene is in school. Shuichi is thinking: We overdid it... Hiro appears!
Hiro: Shuichi, are you leaving early today? Shuichi: Huh? What are you saying, Hiro? Hiro: You don't look too good. You want me to call your folks? Oh, wait! Your parents aren't home right now, are they? They are on a vacation.
Shuichi smiles up at him.
Shuichi: It's nothing. I feel fine!
Hiro doesn't seem to believe him though and Shuichi just laughs nervously. Hiro grabs his hands and messes around.
Shuichi: Waah! Kyaaah! Stop iiiit!
Hiro stops and looks worried.
Hiro: You.. are you really alright? Does it hurt somewhere? Shuichi: Haha! Uhm...
Shuichi thinks: That's because my uniform scratches against "that" whenever I move.
From what I understand Shuichi is super sensitive after his night with Yuki. So everytime he moves and his uniform rubs against sensitive spots he really feels it. Shuichi starts crying and thinks to himself: As if I could tell anyone about that...
Hiro: Shuichi!? Hey! You're not fine at all! Let's go to the infirmary! Should I call an ambulance!? Shuichi: I'm alright...
Shuichi is wondering how long he can keep this up. In the next scene Shuichi is sleeping in the infirmary. Someone enters the room and touches his face. Shuichi thinks it's a nice smell and wakes up to see Yuki bent over him.
Yuki: Hiro called me from your cell phone. He said you weren't feeling well and asked me to pick you up. He was really worried about you. Seems like you got yourself a good friend, huh?
Yuki pulls up Shuichi's shirt and strokes his chest.
Yuki: Talking about you not feeling well; this is the price you pay for being so sensitive.
Shuichi gives him a halfhearted glare. Now comes a part I'm really not sure about. Yuki says something like, that he'd be a bad old man in the eyes of the public authorities and that the correct answer would be that he just came to take Shuichi home.
Shuichi: ... But... it's already happened... in the morning buss. I was touched a lot...
I think he's referring to masturbation. Yuki gives him a catlike smirk.
Yuki: Oh, you were touched a lot? Shuichi: Countless times. But come to think of it, you do it even more, right... Yuki: Oh?
Yuki snickers before kissing Shuichi. I guess they were joking around? Yuki says something about assisting with the touching. They kiss again and Shuichi thinks: This smell is Yuki Eiri's smell.
Shuichi: Wai... Yuki... wait...
Shuichi thinks: I've come to the point where I'm even in love with this persons smell. In the next panel Shuichi is drawn like a chibi (baby style). He looks excited at Yuki and thinks: Will... will we do it here...!? <3 But when Yuki touches Shuichi's erection Shuichi thinks: Wait! That'd be bad! No! I shouldn't react to this!
Yuki: Since it's my fault, you ended up like this, I should take responsibility.
He dives down at Shuichi, who tries to fend him off.
Shuichi: That's okay! You don't have to! D... Don't take off my pants, Yuki! This is my school! Aren't you an adult?! Hey! Old man!
Yuki inserts a finger in Shuichi and licks his nipple.
Shuichi: Hey! This is bad! What time is it... At three o'clock... N... No... We'll be discovered by the nurse...
Shuichi thinks: This is bad... I'm really starting to feel aroused. He continues telling Yuki to stop but his protests grow weaker and weaker. Yuki licks and pinches Shuichi's nipples.
Yuki: Though it doesn't feel good your nipples sure react. Shuichi: Uwaaaa! It feels good! That's baaaad! <3 Yuki: Where does it feel good? Shuichi: Stop it already... <3 Yuki: Here? Shuichi: Ohhh.... my ass too... ohhh... this is baaad... ah... <3
Yuki pleasures Shuichi's ass with his fingers and continues licking his nipples. Yuki looks up at Shuichi.
Yuki: What time is now? Two o'clock? Everyone is in the middle of studying, while Shuichi kun is having "bad" sex. Shuichi: That is... I don't want to be caught by a teacher... please...
Yuki is about to kiss Shuichi.
Yuki: No one will come in here. It's ok. Shuichi: Are you... really going to use it?
He's probably referring to Yuki's dick.
Yuki: Yeah. I'll make you come slowly. Shuichi: Hey... wai... Yuki: Don't cry out.
Yuki enters Shuichi. Shuichi thinks: What am I doing? I've become an idiot. They continue talking dirty. Shuichi keeps protesting half heartedly and Yuki says stuff like: But your body reacts so nicely. Shuichi comes.
Shuichi: I'm... a pervert... I'm way too perverted... <3 Yuki: That's ok. I'm a pervert too. And this perverted monk will start digging around your ass some more. Because I'm making you mine.
We see the window and people outside. Shuichi thinks something like: On the other side of that curtain my everyday life continues while in here, this person is making me his. They keep on having sex and having sex talk. At one point Yuki buries his mouth in Shuichi's neck.
Yuki: Becoming mine... are you really sure about that? Shuichi: Y... Yeah...
We come to the last sex panel where Yuki has pulled out and Shuichi is a mess in the bed. Shuichi thinks: What should I do? I'm so incredibly happy...
In the next scene Yuki stands by the window and Hiro is knocking on the door.
Yuki: Yes. Hiro: Uhm... Yuki san? Oh, it's open.
Hiro opens the door.
Hiro: Sorry to bother you. Is Shuichi still sleeping? Yuki: Oh, Hiro kun. So you came, huh? You're a nice kid. I bet you're popular. Hiro: Huh...? Uh... about Shuichi...
Hiro sees Shuichi.
Hiro: Oh, you're awake? How are you feeling?
Hiro tugs at Shuichi's blanket.
Shuichi: Hir... Hiro! Don't touch me!! Don't get close... Hiro: S... Sorry. Shuichi: I have a cold! So... I don't want you to get sick too.
Yuki confirms Shuichi's story to Hiro and asks Hiro to tell the teacher that Shuichi will be going home early. Shuichi blushes.
Shuichi: Also... earlier... the sheets got dirty so I'll return them, once I've cleaned them. Hiro: Dirty? Did you vomit? Are you really okay? Do you have a fever?
Yuki steps between them and thanks Hiro for having called him. Yuki gives Hiro keys and asks him to return them to a girl called Aika.
Hiro: Uhm... do you mean our nurse? Yuki: Probably her, yeah. Hiro: Why do you have the keys to the infirmary?
Yuki smirks at Hiro.
Yuki: Give her my thanks for lending the keys to me.
Shuichi thinks stuff like: And like in a shoujo manga he swept me up in his arms. I just wanted to squeal like a girl when looking at his face. While seeing the world from a 180 cm perspective, everything leaked out of me from under the autumn wind.