Kaizensei Altruism

 (蓋然性オルトイズム) is an idol group formed in December 2020 by ONEtoONE Agency and includes former members of TEARS.

They debuted on February 1, 2021.

Current Members

 * Makise Yumi (牧瀬裕美; )
 * Tsuji Kaho (辻海帆; )
 * Kawashima Arisu (河島有寿; )
 * Tachibana Ui (立花憂衣; )
 * Mizuue Saki (水上咲; )
 * Kururugi Maho (枢木まほ; )
 * Kanzaki Serina (神崎せりな; ) (Joined March 20, 2021)
 * Kita Conatsu (北こなつ; ) (Joined March 20, 2021)
 * Aikawa Mana (藍川まな; ) (Joined July 23, 2021)
 * Futaba Yui (二葉唯; ) (Joined July 23, 2021)

Former Members

 * Nagatsuki Yuuki (長月優希; ) (Withdrew May 26, 2021)
 * Asahina Nana (朝比奈なな; ) (Graduated June 20, 2021)
 * Shiraishi Neon (白石ねおん; ) (Graduated June 20, 2021)