Once you got into a relationship with a girl, you'd get a message saying "They may get jealous if you go out with another girl" and this basically created a 60 day counter. If you didn't talk to them for 60 days, the link would reverse
If you went out with another girl (I'm not positive if it's just any link with another girl or only ones after you're in a relationship with them too) the counter would instantly drop by 15 days.
So basically you could "cheat" on a girl up to 3 times with no problems. You'd still have some days to talk to them, do an event with them and reset the counter.
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