You could do the same damn thing in Metal Gear Solid 3, except you could also eat it . Granted, Snake didn't seem to like the way rat tasted. You could maybe saute it's brain. I've had squirrel brains (what some North Americans would refer to as 'good vittles') and they're like tough, tasty fruit.
Here's an idea: An unlockable if you pre-ordered. A fork equipped on the bottom of the knife's handle so you can flip it around and eat the fucking rat, assuming the verminous little bastard isn't carrying bubonic plague or some more modern epidemic such as Hanta virus. There's not giving a shit about human death, and then there's championing diseased rodents while simultaneously and un-ironically caring very little about a soldier stepping on a landmine and then needing to have his leg sawed off while you press X to get it through his cartilage and bone, blood all over the screen and screaming.
Let's face it, PETA makes all vegetarians look like they're some kind of druidic animal worshipers, when many are in fact not. Evolution on some scale determines when a species eventually falls out of the chain. . As things are now, the only universal thread rats and other rodents preserve is food for large birds of prey. And even then, such avian species do not poop out a nutrient-rich fertilizer that grows crop better. At one point New Zealand farmers raised a slaughter of the stoat, a tiny weasel mustelid known for wrecking havoc on not only the dwindling kiwi population, but bird species in general. Mustelines are the more clever, war-like cousin of rodents... hunting for youngling eggs, and rabbits. If there are 10 rabbits in an area that a single weasel moves into, they will be dead before winter. Killing a rat---an equally prolific pest--in no way unbalances the circle of life, fools at PETA.