Hum... It's interesting Rakan is face blind (Prosopagnosia). I too, actually am face blind. I absolutely can not tell anything from a person's face.
However, I wouldn't characterize his situation like how Maomao does. He would still be able to identify people (like I can) through other means. Usually, I can tell people apart from their builds, posture, expressions, voice, etc. It's not that hard, and at the extreme, if you say a few words I can figure out who you are pretty easy. Rather, I find it more useful because I can identify many things about a person's posture than I think a person can from their face. In my case at least, a person's face has no meaning to me. Do you have big eyes, or a small nose matters almost nothing to me. That also doesn't mean I can't make out facial expressions, just that I have no point of reference to what face pieces make a person unique.
On a funny story, there are 2 stories that happen because of my face blindness, which I thought was fairly funny. The first is that I had a friend who I known for a long time and did not realize he had cancer as a kid that paralyzed half his face completely (like he can't even close his eyes on that side). To which I never noticed until I went for surgery and he went with me and the nurse pointed it out. He always hated taking pictures of which I literally had no idea why until that point. The other story is I have a close relative that did pageants and stuff at an International level to which I assisted with quite often, but I could not at all describe you how her face looks.
So it's fairly interesting, he has face blindness, but I don't really think it's particularly accurate.