This Guy & I Are Inseparable

College student Ayumu Kurosawa moved out of his parents' house to enjoy anal masturbation without any worries. However, his neighbor turns out to be his childhood friend and first love, Junpei Shiraishi. One night, Junpei unexpectedly sees Ayumu playing by himself using a toy. He casually remarks, “Isn’t this one better?” while pulling out his large d**k...! Ayumu feels annoyed at Junpei’s carelessness, but his body tingles at the thought of having such a big "real thing" inside him...!

(Source: CLLENN, translated)

Note: Includes one extra chapter.