You (deliberately contrarian for the sake of it?)dickhead. The character already was a tomboy (or rather, a female wanting to control her own outcomes in life).
Normally I try not to insult people, and just attack their argument, but sometimes it's just really justified.
Edited: To insert "deliberately contrarian", to specify the behaviour prompting the insult. It's not the person, it's the action. All happy now? :)