I do not know a particular idiom that describes the above, but here is an idiom that might have slightly similar meaning:
Hook up – to meet someone and spend time together; to associate; to become sexually involved with someone.
Yesterday, Jim hooked up with a very nice girl. I think they might start something serious.
He always comes back home late. I think he hooked up with the wrong people.
Here are some idioms about love:
https://www.myenglishteacher.eu/blog/20-suprisingly-funny-idioms-about-love/
