from what I remember, it was a short shoujo manga, with the main story maybe being around 3 chapters, and then one or two side stories. The main story was about a girl who fell in love at first sight with a waiter or a magician I can't remember, and asks him out. He agrees, but also states that he was a weird 'kink' of sorts where he likes tying things up (it's not actually as sexual as it sounds I promise). She says she's fine with it, and she starts living in his apartment, where her hand is tied to a table, kind of like a dog leash, but she's free to go whenever she wants, so long as he's not there when she does so. Anyway, it's revealed at the end that the reason why he ties things up is because

when he was younger, he let go of his little sister's hand when they were playing, and she got hit by a car and died. I would really like to read it again so any help is much appreciated!