Jellal, Mirajane, and Sorano all get really competitive on one day of every month. This day is the B.O.S.E. (pronounced "Boss," Best Oldest Sibling Ever) competition. The winner of this event gets bragging rights and a ribbon with an exclusive picture of their sibling(s). The siblings in question do not understand why its so important, but they cheered on the competitors all the same.
- It’s like Sorano and Jellal argue on who was the worst sibling and least there for their baby siblings (with or without reason) or try to figure out who was the most evil sibling… They figure out that Mirajane turns into a devil, so she wins that round.
- Those races where you carry your siblings on your back and run to a finish line? Jellal carries all of his sisters on his back and Mirajane carries her buff baby brother and little sister; Sorano just carries Yukino with absolute ease.
- The little sisters decorate t-shirts for their teams and share them among their friends with each other - no matter who wins or loses, they’re still the best sibling they’re going to get.
- Big siblings dress up (one) little sibling contest, only given average things you find in a house: trash bag, toilet paper, duct tape, etc.