User blog comment:B214/Question & Answers 5/@comment-66.87.80.53-20150708203348/@comment-16281343-20150709184942

Ishibumi already gave a setting for them.

In the past, Sirzechs only has 3 friends. Ajuka, Serafall, and Falbium.

Sirzechs and Serafall both knew each other as their mothers are classmates when they were students and best friends. Ajuka is his best friend. Falbium, who likes to take afternoon naps, for some reason isn't afraid of him.