Ayane Kotou attends the same school as protagonist Shougo and announces herself as his arranged fiancée, revealing their parents decided the marriage without his knowledge. She explicitly declares she does not yet consider him worthy of the engagement. Her status as the school's most popular girl ignites jealousy among Shougo's classmates following the engagement announcement. Her presence at Shougo's residence coincides with intimate moments involving other characters, creating implied tension.

She shares a history with Shougo, having received a childhood marriage promise from him years prior, which forms part of her established background. Despite the series' harem structure, interactions involving Ayane occur primarily in isolated one-on-one scenarios rather than group dynamics.