Now, for random information that you probably don't care about.

Inui, from the first video, was singing with just the karaoke version of the song. She didn't have the lyrics, she had to go with what she knew.
The second video is my favorite. The girl in the video was cosplaying as Atobe. The wig she bought for her cosplay didn't come in, so her hair didn't look right. The song she sang was from Tenimyu.
In the third video, the person who ran the panel stopped the music and asked if the person who was singing ever tried out for a musical. I don't think you can really hear the question.
In the last video, the girl who was singing could sound like Karupin.

Finally, I was originally going to do the karaoke contest myself, but I decided against it. I was going to sing "You Got Game" by Kimeru. Next year, as Kamio, I don't think I'll be able to get out of it!