Kizuna Volume 1 Deluxe Edition (yaoi)

Kei Enjouji and Ranmaru Samejima are a sweet couple, but their relationship is put to the test when Kei's annoying, bratty half-brother, Kai, decides to make moves on Ranmaru. Three's a crowd - but knowingly, he invites himself over to their home and tries to throw his "wrench" in the plan... which is immediately crushed when Masanori Araki cleverly steers him away. Masanori is the yakuza boss' right-hand man, as well as Kai's life-protector.