I guess in the anime they try to make it a little more kid safe, but Kazuya Minekura-sama (峰倉かずや) doesn't have Hakkai say that Kanan is " like" his sister... she IS his sister, hence why Chin Yisou calls him a sinner. Cha- ch-ch-chaaa.
Amehzing. Their back stories are all so intricate, kudos to the creators. And am I the only one who thinks Hakkai is wayyyy prettier than Kanan? Because he is. In fact, they're all four really pretty.