Talk:Kuroyuri (episode)/@comment-58.170.146.216-20170122200551/@comment-4010415-20170122204903

As an American, I've literally never encountered an example of someone referring to their friend by their family name. I've encountered people preferring to be called by their middle name (especially since one of them disliked his first name), but not that.

I think Ren just prefers to be called Ren, possibly in remembrance of his parents.