Denpa waves are like the emotions of people that reverberate
inside the head of those who are able to sense them. It's a sort of sixth sense, though not quite. It doesn't give any special
powers other than the ability to figure out what goes on inside another's head.
Saki's denpa sees to the essence of matters. Being able to
sense people's idiosyncracies and send her own waves inside people's heads. An incredible ability that anyone would fear.
However, even she can't read Sohma Yuki's or Kyo's waves. There's a black shadow that falls over their thoughts. Especially
the day they went to visit Kyoko's grave, the waves she sensed from Kyo standing in front of the gravestone-- Just what were
the thoughts that was causing such regret...
In the end, living people are the strongest. It's the same
with waves. Dead people's waves are probable so very weak and are wiped out when faced by the strength of people's thoughts
who are living now...
It can also act as a radar. As seen in one of the episodes where Tohru had been crying
by herself, Hanajima and Arisa had found her due to Saki sensing Tohru's specific waves. Therefor it comes
quite handy in all different situations.