[じゅうしぃまんご～] ぱいずりチアリーダーVS搾乳応援団! / [Jushimango] Paizuri Cheerleader VS Sakunyuu Ouendan! DVDISO

If anyone is wondering why all the encodes for this h-anime have such amazingly bad blocking artifacts, it's because the source material has it as well, unless this DVD ISO has somehow been tampered with. It looks like whoever mastered the DVD MPEG-2 didn't quite know what they were doing and ended up commercially releasing it in this state, so what you already have is probably the best you're going to get unless someone's a wizard with deblocking filters.