"You're still dating that chickboy?"

One of Kei's friends asked. While Kei's eyes narrowed, though he showed no reaction. He kept the same smile as he chuckled slightly, no one realizing that the "chickboy" was outside the door eavesdropping

It's not like Chigiri meant to eavesdrop. It was just a coincidence that the moment he was about to enter, was the moment he heard that. And somehow he actually wanted to hear what Kei would reply

After all sometimes even Chigiri needs reassurance