well considering that the average human rectal orfice is 1.5cm wide and 6cm deep (a study i conducted which included 6.02x10^23 test subjects), a pen15 with a 1.5cm width and a 6cm length should suffice.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.