Cheetwo

Cheetwo is s german shepherd mix raised in a lab alongside Vexus.

Cheetwo and vexus remain close until they are finally old enough to be used in experimentation.

Cheetwo is the first to be subjected to this cruelty and he stubbornly blames vexus for lying about keeping him safe.

When cheetwo finally escapes he in a moment of stubborn anger leaves vexus behind 

Cheetwo did return later to try and free vexus snd apologise but the experiments made his sense of direction and memory very poor , he almost imagines it a dream replacing and confusing true events with stories vexus used to tell him.

when vexus and cheetwo finally meet again and cheetwo recalls it all l, vexus is no longer the beloved friend he once knew and he is forced to kill him to save himself.