I know it was mentioned that he just changed his hair color but why do I keep feeling that...

I know it was mentioned that he just changed his hair color but why do I keep feeling that there's an another guy. Like I've seen two different guys in the same photos(blond and black haired guy) before(not sure if it's in Anashin sensei's twitter or IG). Anyway, I can just save this for the later thoughts. Just for the present, what's the deal with this guy Sena. For now, I know that he's the 2nd ml as seen in the covers. I'm wondering whether Anashin sensei will this time make the female lead end up with the other guy. My gosh I'm so curious.