I really don't understand this reasoning. Her sexual preferences are being steered by what is essentially supernatural mind control. She wouldn't be interested in the main character sexually at all if it wasn't for the spell. It was pretty obvious from the very beginning once the main character found out she was a lesbian that he was gonna use a spell. If she turned out to be bisexual without a spell your concerns of that trope from other games would be warranted.
This one fits kinda. Also, LLtP has me operating at a far lower level of suspension of disbelief. Suddenly breaking out tried and proven retardo porn logic would be a tonal trainwreck. It would mesh terribly with the otherwise great writing and setting.
Whenever straight girls in other games suddenly discover that they happen to be bisexual I don't mind all that much tbh, but in LLtP it has plagued Callie for a good long while. It is a huge issue for her, she turned down suitors, she desperately tries to keep her sexuality secret, she jumps at the first true chance at a lesbian relationship with a brainwashed Evelyn. She isn't in her curious phase, she is well into the "Oh shit guys really do absolutely nothing at all for me what do I do?!" Phase. Your spell changes a fundamental part of her identity and has that added element of a prior trusting friendship added onto that as well. I actually like the character. Enogh so that I hesitated to pull that trigger, instead of simply going "meh I want the nice CGs, get on with it" like I would in any other game I am currently following. Its harder to do questionable things to characters I like, II guess.
So after replaying and thinking about it, that alone tells me just how well done the building was done.
