Ryuuichi http://www.pixiv.net/member.php?id=991469

Also known as Drill Chichikuri (Circle)

Fly Phoenix! Surpass the Moon! Touhou Project Doujin released Jan 13 '14 Comedy Food Mokou x Mystia
The Forgotten Umbrella Picked Up by a Corpse Touhou Project Doujin released Oct 9 '17 Comedy Kogasa x Yoshika Yuri
The Stewartia's Attachment Touhou Project Doujin released Oct 9 '17 Benben x Raiko Comedy Ecchi
I Always Liked You! Touhou Project Doujin released Jan 8 '20 Full color Koishi x Utsuho Yuri