Saezuru Tori wa Habatakanai囀る鳥は羽ばたかない (Japanese); 鸣鸟不飞 (Chinese); Saezuru Tori ha Habatakanai; Song Birds Can't Fly; Twittering Birds Never Fly (English); Chú Chim Hót Không Bay (Vietnamese - Tiếng Việt - TV)
Yakuza Yashiro, who only ever loved Kageyama, meets a new bodyguard, Doumeki Chikara. Unfortunately, the latter is impotent. The masochistic, lewd and beautiful yakuza Yashiro and his silent, clumsy, impotent subordinate, Doumeki. This is the story of a man who has never known happiness and of a man who is reborn by getting to know him.