Ah, the penis drawing. A pleasantly gross reminder of how immature we all used to be — and probably still are.

Whether you were overtly obvious with your penis art (i.e. covering the teacher's white board with a huge erection), or preferred the subtle, understated pecker (i.e. tagging every little corner of the school with small shlong drawings), we've all had an experience with x-rated art. 

And I think we expected those moments to stay behind once we graduated high school. But just like capri pants and crop tops (I don't know if either of those are true), penis art is back in style. 

Giphy

PEN15 Club: Members Only Coloring Book is everything you wish you had when you were a teenager. With everything from penis patterns to penis remakes of famous works of art (such as "American Gothic" and "The Last Supper"), this super adult coloring book will have you looking at the male genitalia in whole new light. 

Architects Jen and Mira — who for reasons we can't figure out, are only going by their first names — created the book after being inspired by their work and ability to see erotica pretty much everywhere. 

"Many buildings are clearly just glass and steel erections," they said in an interview with Glamour. "Now, it's spilled over into seeing both [penises] and vaginas in all kinds of things, intentionally or not." 

PEN15 

The $15 dollar book (which also includes some hidden vaginas), is currently gaining support on Indiegogo in hopes colorful phallic drawings to everyone with the mission to make everyone comfortable around penises. 

People who support PEN15's goals financially can receive beer koozies, printable downloads and a secret gift. These lady architects by day and genital art lovers by night will also donating a portion of their sales to promoting comprehensive sex education in schools through Siecus.org, because they're just that cool.