TV-Series
Description
Chika Igarashi is the younger stepbrother of Iroha Igarashi, having been raised alongside her from the age of five. He is a strikingly attractive exchange student who is fluent in English. Chika is characterized by a deep-seated, unrequited affection for Iroha that has persisted since his childhood. This possessiveness fuels his primary role in the story as an antagonist to the central relationship between Iroha and Hikari Tsutsui, whom he confronts as a romantic rival.

Personality-wise, Chika is initially presented as a volatile and tactless individual, physically lashing out at Tsutsui by breaking his glasses. However, his characterization has moments of complexity; upon learning that the broken glasses were a gift from Tsutsui's late grandmother, he voluntarily pays to have them replaced, showing a capacity for honor and fairness. Despite this, he consistently deems Tsutsui unworthy of his sister, finding him unreliable, strange, and dull. Rather than simply issuing orders, he challenges Tsutsui to prove the value of his relationship with Iroha.

A key detail that explains his intense opposition is the revelation that he and Iroha are not related by blood, which positions him as a genuine potential suitor rather than merely an overprotective family member. In his interactions with Iroha, he uses their non-blood relation as a point of pressure, backing her into a corner to question her relationship with Tsutsui. His ultimate motivation is a consuming need to monopolize Iroha's affections, hoping that her relationship will fail.

Within the narrative, Chika serves as the final obstacle in the first season, his sudden appearance designed to test the bond and trust between the main couple. While introduced as a violent and confrontational figure, his role in the larger story arc shows a conflicted shift. When Iroha later undergoes surgery that causes memory loss, Chika initially exploits the situation by omitting details of her past to isolate her from Tsutsui. Yet, he eventually concedes his inability to fully control her life and relays the truth. Years later, he even arranges for Iroha's return to Japan, inadvertently enabling her reunion with Tsutsui, suggesting a muted recognition of her independence despite his often self-serving actions. Chika is portrayed with green hair and blue eyes.
Cast