In April 2022, Rainy. debuted with "Find the truth," the ending theme for "Detective Conan: Zero's Tea Time," the official "Detective Conan" spin-off anime starring the popular character Toru Amuro. The powerful ballad earned high praise, with listeners saying it was "hard to believe she was only 13," and the music video for the song has now surpassed 2.5 million total views on YouTube. She then performed "...and Rescue Me" as the ending theme for the TV anime "Detective Conan" starting in June 2023. From January 2025, she performed "But No Love" as the opening theme for the same anime, and she also appeared as the opening act at the "Detective Conan Special Concert" for two consecutive years. Rainy. will once again perform the ending theme for the TV anime "Detective Conan" with her new song "7 DAYS," starting with the episode airing on June 6, 2026! -- The seven days spent looking forward to the day you can meet someone dear to you can be sweet at times and wistful at others. "7 DAYS" is a pop tune that portrays the frustration of wanting to see someone but being unable to, as well as unspoken, wavering emotions, by likening them to the days of the week. Set to a light country-style sound, the song delicately expresses the sadness of feeling distant from someone even when they are close by.