90210x, your experience sounds a lot like my initial trip to Tokyo: after three days, I was bored and lonely (the only english conversation I had during 6 days was on the train back to Narita because I was lost). I have since been back 3 times, with another trip coming in October.
The things that made the subsequent trips better: knowing the areas better, going with another person, and planning ahead. I understand not liking strip clubs/drinking (I don't care for them either), but give shopping another chance. I think a fun part of travel is to eat/shop like the locals do.
Originally Posted by evergrn
Lot of good suggestions already. I agree with someone who said earlier that it's mostly about having the right mindset... with the right mindset, you'll be able to have a good time in cities that offer far less than Tokyo, let alone Tokyo. Of course, that's easier said than done. I also agree that it'd make the whole thing much easier if you're somehow able to get your friend out of his current mode.
+1^
Hopefully your friend can go along with you--although the summer heat can make it a challenge. If your friend can't, take your camera and capture all the very, very distinct things that make Tokyo such an interesting place.