Lie Detector

Lie Detector (嘘発見器) is the Quirk used by Rai Shinrai and her father Masato Shinrai.

Description
After detecting a lie, Lie Detector allows the user to force the victim to answer truthfully.

With this Quirk, the user can learn the true thoughts, secrets, intentions, and feelings of allies and enemies alike, allowing for information gathering, psychological torture, and prevention of betrayal. The usefulness of this power has apparently made Keito Nakamura value Rai the most out of all the members of Class 1-B.

Weaknesses
It's worth noting, however, that this Quirk is very literal. When Mizuki Camacho and Genki Itzuko were asked if they were told to sneak up on Class 1-B, they said no, as they had simply been told to remember that 1-A was beneath them. Their later attack on Class 1-A was due to their own desires to subdue them.

Lie Detector doesn't have any offensive capabilities, so the user has to rely on other methods to fight directly. Also, given Lie Detector requires both the user and the target to be oral, this Quirk is ineffective if either of them is incapable of speaking.

Usage
Rai uses this Quirk to learn of information that she wants to know, as well as checking to make sure that no one had any intention of lying to her.

In battle, he plays on people's emotions by forcing them to admit things that they are not proud of.