"fuck up my body" Wow, that is an extreme invitation.
Well, let's go with what comes to mind:
1) Lets destroy that ass of yours. Use a brush and get its handle covered in hot sauce and then go fuck your ass with it. Go make it burn.
2) Lets go give your nipples attention as well: Go tie your tits, get your nipples hard and pierce them with needles. You can use sewing needles. Just make sure whatever needles you find that they are disinfected properly before you shove them through your skin.
3) For your ass cheeks, go fetch a belt with a nice heavy belt buckle. Hit yourself with the belt buckle on your ass. Lets go for 100 hits to start with. Go make yourself bruise.
4) On the topic of fucking up your body, lets add another one to your tits. Go tie them and get a rubber band. Push it with 2 fingers into your boob on both ends and grab the middle part to flick it against your boob. Stay on the same spot and repeat until you start bleeding. If it takes you more than 15 minutes, you are not flicking the rubber band hard enough against the same spot. Do this for each boob once.
I usually do not go all out like this in the beginning but lucky you my mood has been quite extreme lately.
If you are willing to show off the aftermath/progress, I will be happy to get some pics/videos @kik(meorin).
Happy suffering.
Meorin