• It is heavily implied that Karin is actually Judas Iscariot, the disciple who betrayed Jesus. Evidence of this can be seen in chapter 109, when she tells Touta a bit of her backstory. She explains she used to have a remarkable teacher, but she ended up betraying him. In one panel, there is a cross and she ends up hanging herself; this is comparable to the account of what happened to Judas, according to the Gospel of Matthew.

• In chapter 129, Negi's hair is parted wrong in a single panel

• In chapter 139, Fate's hair is parted wrong in a single panel