Specific Merlin / Arthur fanfiction research

[tetsuna_uchiha3]

Hi everyone, I'm new to Livejournal and this community. I'm looking for a fanfiction that I read some time ago, I don't remember, but is a Merthur. Unfortunately, I apologize to everyone, but I don't remember much of the fanfiction, but I know that Arthur meets Merlin and the two fall in love, but Merlin explains to Arthur that he (Merlin) does not go beyond the kiss, due of a trauma (which I don't remember ). Arthur says it's okay and they start a slow relationship, but at the same time Merlin wants to overcome this problem and asks Lancelot, who is a doctor and with whom he shares the apartment, to help him, being a therapist. Lancelot accepts proposing to Merlin as an experiment to take off his shirts and touch himself slowly (or maybe only Merlin touches Lancelot , I don't remember apologizing), so that Merlin slowly overcomes his blockade. The problem begins when one day Arthur goes to Merlin's house without warning him (I don't remember the reason) and sees the door open, spying he sees Merlin half naked touching Lancelot also half naked (which for him is a stranger, because if I'm not mistaken he stills , I did not know him). At this point he gets angry because Merlin had told him that he did not go beyond the kiss, instead with another he even came to touch himself shirtless, without knowing that Lancelot is his therapist and that he is helping him, because Merlin would like to go further with Arthur.
I don't remember how the fanfiction continues, I think they will treat again, I hope you can help me find it, I really care about this fanfiction, sorry if I have been too repetitive and long-winded.
Thanks again.:D