Suga Katayanagi's Links
Sachi gives Suga a lot of trouble, but Sachi is more important to him than he lets on. He's not just a family heirloom, but a close friend.
Suga is very important to Sachi. He likes that Suga ignores him a little and that he isn't just an object to him either. Their relationship is complicated, but Sachi wouldn't give it up for the world.