Tech the Bat

Tech is a bat who has an IQ of 298, but she can only use this IQ for electronics, in most other situations such as trying to talk, some people might call her naive and childish.

Personality
Despite Tech's high IQ, she is extremely bashful and often makes mistakes (but are never to do with electronics, more about talking in conversations etc.) and will usually respond to making mistakes with rubbing the back of her head and saying "Oops". Her bashfulness and childishness is one of her main character traits, the other being she is very cheerful most of the time. Some would say her personality is basically Tails' personality except strangely more bashful and childish.

Sonic the Hedgehog
Tech sees Sonic mostly as the "Hedgehog who saves the world", but she also appears to be a bit "lovestruck" over him, but not as much as Amy. She doesn't chase after him, flirt, force him to be her girlfriend at all like Amy does, but she always goes into a love trance whenever she sees Sonic, and will often accidentily call him things such as "Hot", "Cute", etc. when talking about him.

Miles "Tails" Prower
They became friends when Tails saw one of Tech's machines, the Chaos Emerald Inspector Machine, which Tech uses to study Chaos emeralds. Tails was seemingly impressed, and they shortly became friends.

Rouge the Bat
Tech mostly just sees her as a Chaos emerald thief and another bat. Rouge often steals Tech's Chaos emeralds when she's not studying them, making Tech mad at her, making them (sort of?) rivals.

Trivia

 * Tech was originally going to be a prize for someone winning in VanillaTheCat on Scratch's coloring contest. But the appearance was so good the creator (me btw I'm VanillaTheCat ._.) had to keep her. She later become one of Vanilla's best fan characters.