How to Get Your Guy to Open up(2007)

Koibito no Hirakikata

"I... like you, Mr. Ichikawa." The words slip from his mouth as his body temperature rises everywhere he's touched. Natsuki is drawn to art teacher Mr. Ichikawa, so when he hears of Mr. Ichikawa's sudden resignation, he runs to stop him... The art room colored with all their memories together is now fogged up from their hot and heavy breathing... A sensitive, exquisitely romantic ensemble piece written by Aoi Kujyo!

(Source: Renta!)