Sure she can. She's frequently portrayed as straight, and turning Ooi down (sometimes somehow actually being so oblivious she doesn't even realize Ooi is into girls, and blithely trash-talking lesbianism...) mostly for the comedic effect of what Ooi does afterwards
If you take a look at their hourly lines, it becomes evident that Ooi's love for KTKM is pretty much unrequited.
Eh, that's a bit...And showing that kind of slutty face...Kitakami-san will let you do her if you askLemme do you.Isn't there... something you should be saying...?W-Why...We aren't in that kind of relationship, yeah...?K-Kitakami...To think that... Kitakami-san... is het...Before you ask for such things...So do I, Admiral♥I love you! I adore you Kitakami!How do I put this...