Kip could be bisexual, but remember, this film was passed by the Hays Code, so his character couldn't technically pursue men. Amanda Bonner was a beard, and given this film's take on gender roles, it's kind of interesting to see how Amanda's feminism make Kip's sexuality an open book for interpretation.
I think he does have a fondness for her, but I don't think its true love. She isn't exactly pursuing an emotional affair with him, but he wants an emotional affair with her. The Hays Code makes this messy, but the comedy is a mess in a good way.