Loop Nishigori is one of the triplet daughters of Yuuko Nishigori and Takeshi Nishigori, born into the family that runs the Ice Castle Hasetsu skating rink. She is six years old and lives in the town of Hasetsu, Japan. In terms of appearance, Loop has brown hair and brown eyes; she is often seen wearing a pink color scheme and has her hair styled in a ponytail.

As a child character, Loop does not have a deeply explored personality, but she is shown to be lively and curious, typical of a six-year-old. She and her sisters share a fondness for social media, and it is this interest that sets the central plot of the series in motion. Without their parents' permission, Loop, together with her sisters Axel and Lutz, recorded a video of Yuuri Katsuki spontaneously performing Victor Nikiforov's routine Stay Close to Me at the rink and uploaded it to the internet. The video went viral, which directly led to Victor Nikiforov coming to Hasetsu to become Yuuri's coach.

Loop's primary role in the story is as a supporting character who inadvertently catalyzes the main narrative. She does not have a personal character arc or development over the course of the series, remaining a static presence as part of the Nishigori family and the local community surrounding Ice Castle Hasetsu. Her key relationships are with her parents and her two sisters, with whom she is almost always seen interacting. She has no notable abilities related to skating or any other skill; her significance is purely tied to the viral video incident. Throughout the anime, Loop is depicted as an ordinary child who enjoys playing and spending time with her family.