[MILD NSFW] neuron activation (Patreon)

I was rly wondering what to draw today but my period came and now it’s my enemy, BUT that is actually not relevant to anything I just felt like bitching. Anyway amongst the many things that I want to draw cataloged in my brain, lower back tattoos has been reoccurring. And Laurentia was right there so yk… maths! I like to think that the tattoo was so unexpected for Marcello that his brain unlocked instantly upon seeing it (his new fav things)