After picking up Eris' panties, speak to the old guy on Friday morning to give it to him, then on weekend mornings you can train with him. I dont think he has a bubble on Friday morning so that's why you may have missed him, he's the old guy in the bottom of that screenshot.
If he isnt there then try to wait until next week Friday and see if he's there. If he still isn't, then just use MTool to just cheat agility stats.
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