The last thing anyone expected was for the older twin to manifest Cloud Flames. (Or the one in which Tsuna is Xanxus' Cloud Guardian, flat-out terrifies anyone who's heard about him, has a younger brother who loves him, is possibly in a queerplatonic long-distance relationship with Hibari but will never admit it, and is the big brother you never knew you wanted in your life.)

In which Tsuna isn't Tsuna but Tsunako, and lived with her parents in Italy for a few years before circumstances made moving to Namimori seem advisable. And changes spiral out from there. For the prompt Xanxus/Tsuna - genderswap; "don't look down on me because I'm a woman."