Inaka no Musume-san to Ecchi ~Kasoka no Susunda Mura ni Yobarete~
Koi no Riron Ai no Houteishiki
(C59) [Tomoyosama (Kayama Akihiro, Ozawa Hiroe)] Tomoyo No Yasashii Houteishiki (Cardcaptor Sakura)
[poza] Shishunki no Otokonoko no Tame no Seikyouiku Onnanoko o Ninshin saseru Tame no Nakadashi Sex Nyuumon
Caenis to Sugosu Kyuujitsu
[Carn] natsu×umi=Kiken no Houteishiki (Shinzui SUMMER Ver. Vol. 2) [Decensored]
[Azuki Kurenai] Yoru no Houteishiki 1 | Equation of the Night 1
[Bousou Tenshi-UPsideDOWN (Sakatani Shinnosuke)] Koi no Renritsu Houteishiki (Yu-Gi-Oh! GX)
Aijou Seikatsu
[Gentsuki] Yasashiisa no Houteishiki - Tender equation (COMIC BAVEL 2017-08) [Chinese] [揮淚錦馬超漢化] [Digital]
(SC29) [PETS (rin, kuro, may)] Nisemono (Naruto) [English]
(C74) [Momonga Club (Hayashibara Hikari)] Shoujo no Houteishiki - Girls of Equation
Neji to Nejiana no Houteishiki
[Hiyoshi Hana] Chigiri to Musubi no Houteishiki - Equation of Chigiri & Musubi [Digital]