Soul Multiplicity generates a reaction when it tries to merge two or more souls because they naturally try to reject the fusion. By increasing the energy of the souls associated with this effect, the user can generate an overwhelming output of transfigured humans fused into one attack.
Mahito uses Body Repel as a special mid-range attack that greatly adds to the unpredictability aspect of his offense. Body Repel can take many different forms, in fact, it has looked different every time Mahito has unleashed it.
The first time Mahito used this technique he targetted numerous non-sorcerers in a crowd during his group's battle with Satoru Gojo. Mahito and Choso worked together, using Supernova and Body Repel at the same time to cut down several civilians surrounding Satoru.
Mahito used this technique again, but a much more focused version against Yuji. After combining two small transfigured humans' souls, Mahito unleashed a horde of transfigured flesh shaped into a large monster. The elongated beast attempted to bite and swallow Yuji whole with its giant teeth. Yuji was able to stop it with his brute strength, but Mahito appeared from inside the creature and landed a clean shot to his adversary's face.
In order to counter the switching ability of Aoi Todo's Boogie Woogie, Mahito unleashed a Body Repel that created several long snake-like heads with giant mouths that attempted to chomp his targets from every direction. It created such a high volume of attacks that it broke through underground Shibuya into the streets above.
Once the attack concluded, Body Repel solidified together to create a platform for the battle. After keeping Todo busy with a Polymorphic Soul Isomer, Mahito went all out on Yuji by activating Body Repel. He generated more long transfigured mouths to attack and bite at his opponent. This time Body Repel was made more powerful by the increased volume of heads and the scale-like spikes added to them.