Theory 1: Unknowledgeable Kill
This one is pretty tricky. It involves 2 sets of 1-way portals. It will kill both victims if done correctly. Anyways, place the portals here.
Now you see, when the victim on the left eats food, he will fully chew, and taste the food. He will think he has successfully eaten the food. When it gets to a certain point before the stomach, Blue Portal 1 will send the food to the stomach of the person on the right instead. The second person will digest the food, and before it leaves the body, blue portal 2 send it back to the first person. The first person will then shit it out. The first person will have no idea that he didn't digest anything, and eventually die of starvation and not even know why. Assuming the portals are one way, and orange does not send back to blue, then person 2 will also eat twice as much and get really fat and eventually die of obesity. When both parties die, the portals will go away and it will not be traceable back to you in any way.
Theory 2: Shit Anywhere
This is much simpler. Just have a toilet nobody else uses, or one-way portals, to prevent extreme discomfort.
If blue portal is inside your pants and underpants, then you can use the bathroom while walking around, or sitting literally anywhere, and it will go directly into the toilet. Orange portal does not have to be in toilet. If you would perfer to put orange portal in ex girlfriends bed, that also is acceptable.
Theory 3: Playing With Yourself
Everybody plays RuneScape. But when you have more than one account, how are you supposed to get the 2 to interact with eachother? They can't be on the same IP address. But with Portals, this is possible.
Simply run from computer to computer to have your runescape accounts trade, fight, or complete a quest together. This will also get you exercise!
Theory 4: Free Chicken Nuggets
I am telling you how to do this because I am displeased with the chicken nuggets I got from Wendy's yesterday. Usually they are awesome, but when you have a literally mentally handicapped person running the frier, they come out terrible. I don't want to pay for chicken nuggets again. This is another simple theory.