Well, there you go. I expect regular readers would have guessed the pun before even reaching the end of panel one.

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2013-03-16 Painful, 5.0 out of 5 based on 2 ratings
↓ Transcript
1. I can't walk into town with aching legs -- I'll take a pain killer
2. Why don't you take the bus
3. ...
4. I doubt we'd have a glass of water big enough.