User blog comment:Chichiryuushintei/High School DxD BorN Episode 5 Review/@comment-1359322-20150503111305/@comment-26209278-20150503112256

I was thinking that too, seems like they just stumbled on each other or something, but maybe they'll have a more in depth look into it if they ever get that far into the anime, like there was for Kiba in the LN. He had the initial backstory, then a more in depth one later on....