"Baby, you need to...relax a little," he insists, starting to become worried about your new infatuation, "She's my ex for a reason."

Of course she is, you trust Asahi. You know why he's with you now. But does that stop you from comparing yourself to the girl he loved before? The one before you who he probably imagined a future with? Maybe talked about marriage and kids...you don't want to think that much into it, it makes you sick in the gut. But the point still stands.