Brotherhood Failed Successfully

When his first love breaks his heart, college student Fusuke goes to a bar to drown his sorrows, where he meets a guy named Seri and drunkenly tumbles into bed with him. Now, Fusuke's no stranger to one-night stands, but it was always with girls before! Struggling to process everything the morning after, he bails out of the hotel room...only to find out later that Seri is his new stepbrother?! And what's worse, his dad's being transferred overseas and taking his new wife along, so now Fusuke has to live with Seri?! To Fusuke's dismay, Seri clearly has no plans of keeping his hands to himself, but despite all appearances also won't admit to having romantic intentions...and soon enough Fusuke is at his wit's end just trying to keep his head on straight!

(Source: MangaPlaza)

Note: Includes two extra chapters.