The premise of breaking up in Tokyo

The prerequisite for breaking up: You need to have a girlfriend. — "You said you only liked me." "So what if I have one more? We loved each other, we didn't, so let's break up." *** "Why were you secretly contacting your ex-girlfriend behind my back?" "You were stalking me? You've disappointed me so much, let's break up." *** "What's your relationship with the widow next door?" "That's none of your business, don't pry... If you ask again, we're breaking up."