This boy if tamed makes your dinos able to lay more eggs
More eggs = More kibbles or Dino Army
The higher this guy's lvl is the more it boosts up the chance to get twins or triplets if you add the unicorn which does the same thing you'll almost always get twins or triplets so if you want to make an army of dinos oviraptor + unicorn is the best but you can't find more unicorns at the same time and in single player (i think) only one will spawn and no other unicorn will ever spawn in there.
But if you just want kibbles then you need only the oviraptor.
At the start he is useless, but if you're preparing to do boss fights, raids or hard tames that require kibbles to complete them easier this guy is useful, the only bad thing Is that the best way to tame one is with giga eggs
Everyone needs to know and it is dev confirmed that Oviraptors DO NOT buff chances of mutations or twins or triplets. This is a long going myth that needs to be shut down. Any twins or triplets you are getting is purely coincidence. This was said by one of the devs on twitter!