If you see the dialogue between Imoen and Keldorn in
ToB then you would see that Keldorn would more than likely not consider a romance between someone of the PC's age, and Imoen and the PC are the same age more or less.
Keldorn: Imoen! What... are you pawing at me yet again? Do you think I do not notice? You are attempting to pickpocket me, aren't you?!
Imoen: Well, no... I just...
Keldorn: Just what? Out with it, girl. I won't have a party member stealing from me.
Imoen: No, no, that's not it! I... I was just... I was just trying to find out if you're as muscular under your armor as you look.
Keldorn: Eh? What's this?
Imoen: Oh, I know that you're married and all that, Keldorn... but do you have *any* idea how good you look? I... I can't help myself, I just want to touch you all the time!
Keldorn: Imoen! I... I have a daughter that is the same age as you!
Imoen: I don't know what it is, Keldorn... maybe it's the Bhaal essence in me. I just want to run my fingers through your hair and nibble on your ears! Oh, Keldorn, you drive me so wild!
Keldorn: By Torm, no! This is terrible! I... I had no idea I had this effect on you...
Imoen: Oh, get over yourself already, Keldorn! Sheesh. (giggle!) Here's your ring back. I won't take it again, I promise.
Sure, get the PC to say she likes Keldorn... but it's beyond him to like the PC that way, he'd feel like he's 'romancing' his daughter, more than likely. It's one of those impossible romances, sorry to say.
It's my nature...
