"If we keep going like this, we'll lose interest in each other as members of the opposite sex." They met and married through a university club as seniors and juniors. The wife had only experienced sex with her husband and lacked variety, so they even tried watching AV together, but they've been sexless for the past five years. Then, due to work, they had to do figure drawing using the wife and a male student as models. Seeing his wife embarrassed under the gaze of many, he felt excited and couldn't stop imagining her being embraced by other men.
