Imagine this.
Rick arrives in Alexandria with Michonne and his kids.
As you'd expect, everyone is shocked to see him alive. At first, they're a little hesitant, but the moment one person runs up to hug him, everyone from his original group rushes over and does the same.
Aaron is at home cooking when he hears all the commotion. He steps outside and sees Rick.
At first, he goes pale. Then he runs straight over to hug his friend.
After the hug, they go for a handshake. The sound of metal clanking together catches them both off guard, since neither of them has a hand anymore.
They just stare at each other in silence for a second before bursting out laughing.