You know, having the comic helps me realize some details that weren't that obvious in-game.
Mammon and Beel have theirs open, and Beel isn't even wearing the tie. One's too cool and trendy, and the other doesn't really care.
Lucifer's is the longest, plus he has that high neck and the gloves. He's the most guarded and reserved out of all the brothers, so it makes sense in his design for him to not only not show skin, but to wear the heaviest layers in comparison to the rest of the characters.
Satan is, probably, the only one who perfectly wears the uniform (appearances), yet he wears a bow tie. It could be his sign of rebellion and an attempt to make himself unique while wearing the same outfit as everyone else (every other student wears a tie).
Asmo doesn't wear a tie or a bow tie, either, but he does wear a bow of sorts (and now that I've written all of that together, it also ties the two of them as having a closer relationship inside the family dynamic). However, and although his uniform also looks impeccable, Asmo wears his belt as a bow (and is tied higher and tighter around his waist), which creates the illusion of his coat being a skirt or a mini dress! Plus, his legs are crossed in place, which is a very feminine way to stand. (And I'm saying this like blue = boys ; pink = girls. It doesn't have to be like that all the time, but it is the stereotype).
You can see it's his belt because the buckle is at the end right there.
dededos
blakekathryn
areudirty
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