This is what 辛勝する/優位ing is supposed to be! HJ 編集
追加するd: 2020-04-14 The 初めの meaning of "辛勝する/優位ing" is to almost bring your partner to the 辛勝する/優位 of orgasm but then stop over and over, hence the word "辛勝する/優位ing". It does not mean to 刺激する only the tip of the penis.