Hey RubixRamen (I take it that your name is a love letter to Ramen? Great stuff!)
There are definitely planned romance options which will weigh in more in the 2nd chapter but I actually never thought about the player character/guardian spirit being an option. It's a really interesting but somewhat abstract idea - falling in love with someone who's appearance you don't really see but is part of your mind.
What I can share with you are the already mentioned upcoming romance options! :) There will be some scenes & situations you'll definitely enjoy, I'm sure! Thank you for your feedback!