User can let out enough heat to make others around them warmer.

Pros:
-User controls this freely
-User can eat mildly spicy goods
-If a girl, cramps would be no trouble whatsoever
-user requires little food to produce heat

Cons:
-user will get a light burn if overused
-user must constantly drink water during summer

Weakness: unknown

This quirk is unlikely to be used for hero work and more for support. User may also treat hypothermia when there is no heat around.
There is no physical advantages.

Also not joking about the "help with periods thing", it would be heaven with very sore cramps