Who is Patroclus?

Patroclus is a good warrior and comrade. But with his stubborness, he met his end. Not following Achilles' warning, he still pursued bloodshed with the Greeks. Patroclus can be described as a wild and reckless warrior for what he has done. Lastly, based on Achilles' emotion when Patroclus died, I can say that he is really a good warrior and comrade that Achilles might be of revenge.