n. boobwarmer: refers to the space in between the top and/or bra and the boobs where the hands go, in there the hands are warmed due to the warm heat from the boobs being trapped by the top and/or bra
verb. to boobwarm: When one puts their hands into a girl's top and/ or bra in order to warm up said hands. Also works with anyone else's hands not necessarily the hands of the body the boobs are a part of.
Viktorea was cold so she put her hands in her boobwarmers.