You'll meet the reason he doesn't like girls around chapter 9 or 10, I think, and find out where his facial scar came from. Also, Hanako always hogs the Meatopia bars...
He gradually opens up to Rozalin though; he's a huge Pleinair fan (if you download her); and he never shows any interest in guys (beyond the "KILL ZENON!" thing). So no, he's not gay. He's just a closet fight-freak in denial of his true bloodlust...who also had one bad experience with a woman in the past.
Wait, who's convincing themselves of what and failing, again? o.o
So far, other than the post that a moderator ate, this topic has been very tame and straightforward. CFloBucket actually managed to put together a topic on this subject that didn't degrade into insult flinging, so I'm very impressed. ^^
Another thing to note is that, even if you don't get the Best Ending, Adell and Rozalin's Team Attack Chance just keeps on getting better every chapter, as a way of hinting that they become more compatible. They're definitely a couple.