Team Kenzi!
"Basically what she said," Natasha indicated with a glance over at Ruby, out of the corner of her eye. "Pull the pin and throw, don't hang onto it. It'll hopefully take care of the rest of the mess." Maybe with fires, stuff blowing up, but it wasn't going to be their concern - because now that the rift had been closed, sealed off, there was no reason to stick around and stare at it.
She really hoped that Ruby didn't get anything blown off - while Natasha had taken it upon herself to begin self-defense training with the other residents and be in charge of weapons administration, she wanted to get in a few lessons first. Don't hold a grenade seemed like a given, anyway.
Knives sheathed back where they belonged, after wiping off the demon blood, she remained on alert and ready to turn tail and run at high speed.