In fact TWO Grimm x Ichi fics
One is called Love Lessons - an AU teacher Grimm x Student Ichi fic.
http://www.fanfiction.net/s/4091001/1/Love_Lessons and the other Sing To Me - an AU rock star Grimm x Ichi fic.
http://www.fanfiction.net/s/4091722/1/Sing_To_Me Hope you enjoy!
This was x-posted to other comms! I apologize if you read it a lot!