Shisui is a slut for Itachi's blow jobs. He would never admit it to Itachi, but Itachi is way, way better at giving head than Shisui is. He has a way of twirling his tongue around Shisui's dick that makes him go mental. Itachi would often start slow, taking it in and out only a short distance, then look up at Shisui with those glistening, kind eyes of his that made Shisui want to both protect Itachi from all evil and fuck him unconscious at the same time. He would then deep-throat all the way to the shaft, over and over again and make these hot, mewling sounds that made Shisui come in seconds. Itachi would fill his mouth with Shisui's semen, then look up at him with shy eyes, asking for permission. He can't hold it all in; so some of it leaks out of the corner of his mouth. Shisui would lick it up playfully, then whisper "Please..." into Itachi's ear. It's not a plea, no matter the wording, and Itachi knows it when he swallows.

It's never enough enough; seconds after having emptied himself, his erection was alive and throbbing, wanting to penetrate, to conquer, to feel, all that was Itachi.