How the Nerd Investigates

[I think I finally caught their tail.] Do-yu infiltrates the academy to find the 'criminal', a wizard who causes chaos in society. All of the victims at the academy were nerd students. In the end, he pretends to be a nerd and starts investigating under the orders of the team leader. Even after a month of investigation, the students are busy avoiding him. While there was no progress, Cheong-shin, a popular star at the academy, suddenly approaches him first. Do-yu is convinced that he must be the criminal because he is strangely fond of him... [Preview] "It's so cute even when you're flustered, senior. You're so cute that I want to bite you. Can I lick you?" You said you wanted to bite me, ...