Another one of Paul's cohorts, Titus, is hanging around Corinth being a disciple and generally defending Paul's good name.
In the first part of 2 Corinthians, it's Titus who delivers to good news that the Corinthians aren't mad at Paul after he writes a strongly worded letter to them (2 Corinthians 7). So Paul is pretty overjoyed with the messenger here. Titus is also really impressed by the Corinthians' turn around. We guess he wasn't holding out a lot of hope.
Later, Paul sends Titus along to Corinth to start collecting money for Christians in Jerusalem. He calls Titus "my partner and co-worker in your service" (2 Corinthians 8:23). That's sweet. But Titus has his work cut out for him. In the second half of 2 Corinthians, it seems that none of the promised cash has been offered. Paul still has Titus' back, though. These guys are tight.
Throughout the letters, Titus functions as yet another witness on behalf of Paul. Paul invokes Titus's name to assure the Corinthians that he's not trying to scam them or anything (2 Corinthians 12:18). He also tells the community how much he would brag about them to Titus and that, luckily, Titus got to see their general awesomeness firsthand (2 Corinthians 7:14). Whew. That was a close one.
Titus shows up a couple other times in the Bible. In Galatians, Paul says that Titus accompanied him on a trip to Jerusalem. Since Titus wasn't circumcised, this caused a bit of a fervor, but Paul stood firm. No circumcision for Gentile Christians necessary (Galatians 2). Titus also gets his own non-Pauline biblical book. The Epistle to Titus is addressed to him. You go, Titus!