RR acting like a one man shield does define his character. There are so many good, interesting things being said about him as a man.
He believes in justice, right-and-wrong, and family. To RR, the Shield is necessary and always will be. Dean and Seth are his brothers and always will be. For now, he'll be The Shield alone but he believes his brothers will come back and he will welcome them with open arms when they do.
He's the ultimate good guy. His character is displaying incredible loyalty and focus.
I wish I could find it but there's a match where he says to Rollins, "You're still my brother!" and it was a very touching moment that showed a lot about his character. I couldn't care less about Ambrose wanting to beat up Rollins for revenge - I care a lot about Roman wanting to know why his brother betrayed him but loving him regardless.
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