One of the most wonderful peculiarities about Fullmetal Alchemist is that its characters cannot be easily reduced to stereotypes, or their qualities labeled as clichés. You could perhaps think so at the beginning, but digging a little further you realise nothing is as easy as it seems in this manga. Of course, Roy being such a complex character, there are other little details or quirks that make him what he is.

     

Roy plays chess. We've seen him playing against General Grumman in chapter 25 and against Second Lieutenant Breda in a color illustration. Roy's skills are never discussed straightforwardly, though. Grumman claimed to have beaten Roy 97 times and tied with him 15. Roy's first win against him was also his last match before being assigned to Central City. Not everyone will agree with me, but considering his way of playing at that time and also considering Roy himself, it's not difficult to imagine he lost all those times on purpose.

Think about it. General Grumman is a kind old man, a general who's in charge of East Headquarters and also Hawkeye's grandfather. He's one of the few people in the military who may be trusted, he's rather fond of Roy and even goes as far as offering her granddaughter as Roy's (the future Fuhrer's, as he says) wife. It's not hard to think Roy would have liked to let the man win, out of respect, fondness or just because he wanted to keep the man happy. He's his superior after all. Who knows, maybe it'll all get clarified someday.

Roy is very much a dog person, despite not being the one to keep Black Hayate at the end (and after delivering what can only be described as a lunatic rant on dog slavery). Still, it's obvious he's very fond of Hawkeye's dog, he's even been seen trying to feed the dog from time to time.

As strange as it may sound, we know quite a bit about Roy's sleeping habits. He sleeps on his side while hugging his pillow, with his mouth slightly open. He doesn't snore, nor sleeptalk. It looks like he can get straight up in case of an emergency, but according to him, he's gotten a little rusty through the years without war in that respect.

Roy knows how to cook. Although it seems his food doesn't taste good... nor bad. More like an indescribable taste. He hasn't ever been shown smoking, and drinking only in illustrations (the one in which he's playing chess with Breda) and omakes (during his 30th birthday). He also knows how to drive, as we could see in chapter 37 (and the followings) and chapter 48.