TV-Series
Description
Kasuga Shinichi is the father of the protagonist, Yui Kasuga, and appears as a secondary character throughout the anime. He is approximately thirty years old and married to Sakura Kasuga, Yui's mother.

In terms of personality, Shinichi is depicted as a cheerful and jovial man, maintaining a friendly and approachable demeanor. A defining trait of his character is his overprotectiveness towards his daughter, Yui. He is notably wary of any boys showing interest in her, which becomes a source of humor and conflict, particularly regarding his feelings towards Yui's friend or love interest, Shun. This behavior marks him as a doting parent who tends to treat his daughter as younger than she is. The close and affectionate relationship between Yui and her father is a notable aspect of her family life and a contrast to some of her friends' home situations.

Professionally, Shinichi works at a company that creates entertainment websites for the RedCom, the virtual network central to the story. He is part of a team of computer engineers and is specifically credited with creating sites such as Galactic World and Undersea Adventure World. A recurring plot point involves these websites containing hidden areas that have been compromised by viruses, which often leads to the need for Yui and the Correctors to intervene.

Shinichi's role in the story is primarily to serve as a motivating and grounding presence for Yui in the real world. His connection to the digital realm, through his work as a website creator, frequently places him in situations where the conflict between the real world and the RedCom intersects. This is evident early in the series, where he becomes trapped within the net during an attack, an event that significantly influences Yui's decision to accept her role as a Corrector. He is a supportive figure in his daughter's life, though he remains unaware of her secret identity as a magical girl fighting viruses online. His relationships are centered on his family; he is depicted as a good friend to the character Chef Kirsch, but his most significant bond is his loving and protective relationship with his wife and daughter. He does not possess any notable fantastic or digital abilities himself, as his skills are rooted in his professional expertise as a computer programmer and web designer.