Stray Cat(2006)

Suteneko no Karute

Kaoru is frustrated -- he's just been dumped by his boyfriend again! And it's all because he could never express his true feelings properly. What's wrong with him?! Feeling lonely and miserable, he takes a stroll through a gay park one day and meets a straight guy named Youhei. Although he seems to be an unassuming, gentle soul, something inside Youhei has caused Kaoru's heart to swell. Will Kaoru step out and express his feelings to Youhei?

(Source: BLU Manga)