Y'know I find it hilariously very stoopid that they need to get A rank in order to switch partner. Like you have to make the pseudo relationship works the best to get out of that ???? Isnt the reason people get out of relationship because its not workin out ?? But oh well~ it is what it is
To be fair, they did make it obvious that the reason for that is so they can explore relationships with other people. They don't HAVE to, but they want them to be able to have a good relationship before considering doing so. The fact that there isn't a factor for those doing poorly as well, because maybe they have poor compatibility to begin with, though, is pretty terrible.
Lastly, god damn that "friend" is super annoying and adds nothing good to the story.