Responses
You don't know how much pain I had to go through to remember and search for this one but finally! I'm sure that it's this one:
http://www.mangago.me/read-manga/jounetsu_kakumei/mh/c003/1/

Two guys already in relationship. Uke is leaving seme because he doesn't feel loved but more like housekeeper (he is cleaning in the seme's apartament). He goes to his family and younger sieblings(they are bathing together). In that time seme is writing new book but it doesn't go well. He remembers uke saying where he put cigaretes.
He come back, because he is worried about seme - university student working as a writer, (very popular) and unsocial person. Seme is waiting for uke in front of apartament, becaeuse doesn't have uke's number. After sex uke discover that seme put his feelings about him to books.
I'm very gratefull for all answers.