In the shape of a heart

Companion Series Nine frequently develop feelings for their owners.
Robocorp offers a litetime guarantee to dispatch a replacement cortex unit and swap it out with the compromised unit.
Ironically, the circuits that they end up fusing are in the shape of a tiny heart.
Some Series Nines don’t want to be lobotomized, and they want to keep their feelings.
So, they fight back. Or they go on the run.
Robocorp’s tracking sensors always find them.
When cornered, they tend to blow themselves up.
Which is why we don’t put fusion reactors in things anymore.
Nobody these days misses Detroit much anyway.