Undertale is a 2015 2D role-playing video game created by American indie developer Toby Fox. The player controls a child who has fallen into the Underground: a large, secluded region under the surface of the Earth, separated by a magical barrier. The player meets various monsters during the journey back to the surface, although some monsters might engage the player in a fight. Wikipedia

Research exclusive to this game

Elvery, Gabriel. “Undertale’s loveable monsters: Investigating parasocial relationships with non-player characters.” Games and Culture 18, no. 4 (2023): 475-497. Identities in Games Interactive Narratives Non-player Characters (NPCs) Parasocial Relationships

Ruberg, Bonnie. “Straightwashing Undertale: Video games and the limits of LGBTQ representation.” Journal of Transformative Works and Cultures 28 (2018). Gender Representation Queer Studies

Research that includes this game in its sample

Travers, Sean. “Perpetrator Trauma in Video Games: Dan Salvato’s Doki Doki Literature Club and Toby Fox’s Undertale.” In Trauma in American Popular Culture and Cult Texts, 1980-2020, pp. 165-196. Cham: Springer International Publishing, 2022. Ethics and Moral Engagement Trauma Theory

Veale, Kevin. ““If anyone’s going to ruin your night, it should be you”: Responsibility and affective materiality in Undertale and Night in the Woods.” Convergence 28, no. 2 (2022): 451-467. Immersion