Escape From Another World summary:

Kim Seojoon, a freshman college student leading a normal daily life, awoke one day to find himself transported into a fantasy world straight out of a webtoon or web novel or something like that. As he began to get excited about potentially having the role of a male lead character, a shocking event unfolded before his eyes—a murder of an imperial family. Consequently, Kim Seojoon found himself imprisoned in the world's prison, 'Gehenna'. Will he be able to navigate the treacherous paths of this unfamiliar world?