You was in an argument with Satoru and now you told him to hang up and called his another girl, sarcastically. And he actually hanged up but before you could get more furious he called you once again.

“Can I speak to personality #7? Because personality #4 is tripping.”

He mocked you with his annoying attitude, even though it was just a phone call you can see him smiling at you. Making you wanted to punch him through the phone call.