Aimai Na Kankei

From ‘Mijuku na Kareshi’
Summary (by torrentchan):
Yet another great oneshot from the infamous Masara Minase! This oneshot is about Satoru, a single bussiness man whom had lived alone since high school. One rainy night, Satoru picked up a high school male stranger and give him shelter. Little does Satoru knows that this high school boy might be his dreamfilled escapade. After all…
Note: There is also a follow up oneshot called ‘Yasashiku Toraete (Capture Gently)
According to MyAnimeList, this is part of a collection of one shots. The order goes like this:
1) Aimai na Kankei
2) Yasashiku Toraete; sequel to (1)
3) Itsuwari no Daishou (False Compensation)
4) Man On!
5) Kodomo Ijou Otona Miman
6) Sweet Restraint; (Amai Kousoku)
7) Miracles Don’t Happen (Kiseki wa Okorenai)
8) Mijuku na Kareshi; extra to (7); (Childish Feelings; Immature Feelings)