It is a reference to a famous comedy sketch from Japan. A group of guys is talking about what scares them. One of the guys says that Manju scares him and decides to leave because the Manju talk made him sick. They decide to prank him and send a bunch of Manju to his house. He immediately eats it all saying, "I love Manju so much it's scary." The other guys get angry and demand to know what really makes him angry. He tells them, "right now, I'm really scared of hot tea." I think this oneshot does a good job of turning the sketch into a legit horror story.