I don't recall the OP mentioning it was a romance novel. Maybe I missed something along the threaded path.
depends on the message Your trying to convey. Does the underdog get the girl? Does the sport guy show her the errors of her slothenly ways? All in the build up
Slothenly is not in the dictionary. (Even the online spelling checker complains...) Slovenly or slothful? Two different meanings apply to the two different words.