I found this manga one day on the internet and it remains one of my favourite things. It's a take on the typical romance manga which tends to operate on a constant "will they, won't they, oh they almost did 1000 times but everyone's in excruciating nervous teenage denial of their feelings" theme. The premise is that the characters wake up one day to find that their sentient penises have body-swapped (or, uh, penis-swapped).
What I love about this manga is the caricaturisation of the typical, the cutesy/chibi style contrasting with the lewd, and ridiculous story. I love the rudeness combined with cuteness.
Please enjoy some choice screenshots below.
You can read Chintsubu here.