Hm, stealth or detection?

[i]"Ai's Semblance allows her to use her aura to control her presence. While active, her aura is disguised and is difficult to detect, letting her move without making a sound, but her aura can also be used to exert the uncomfortable feeling of being watched by an unseen predator."[/i]

[i]"When Ai activates her Semblance, she becomes hyper-aware of the environment around her and of herself, letting her move without making a sound. Both the presence of aura (Humans and Faunus) and the total lack of aura (Grimm, their lack of an aura stands out against the background noise) are easily sensed."[/i]