Remember, in the framework that it is presented, this is a mindflayer digging through your brain to find out who you fantasize about. This could have all sorts of applications later on.
If that's all it is, or if all it is "build what your romantic interest looks like", I won't be impressed. There are many different possibilities for missing a person or looking for them or thinking about them, and if you're shoe-horned only into fantasy romance, that will make Custom Characters seem underwhelming, because it'll be the same thing each and every time.
I'm not actually sure why the Mind Flayer would care, because as far as it is concerned, we'll be another part of the hive in a week anyway.