I have a coworker who's doing all of our UI and screen designs. Every time he has finished a design he immediately wants to talk about it and randomly calls. Sometimes when he spots small errors in a live project ("this looks a bit wonky in Safari", "the headline here needs three pixels more margin"), he wants me to immediately fix them and gets pissed when I finish my current task first.
Dude, we all have work to do here, yours isn't (always) the most important one. I am very close to escalating this to my boss, because it gets increasingly difficult to ignore it and sometimes it feels like he's cosplaying as my manager.
In short: I hate getting interrupted when I'm in the middle of a task and I hate someone breathing down my neck. I'll get to it when I get to it.