I wasn’t completely sure where this fitted into continuity, but since Norman isn’t missing and Peter and Gwen are back together it appears to come after Spectacular Spider-Man Magazine #2.
There’s actually three stories in this comic and the one we’re after is “The Reprehensible Riddle of… the Sorcerer!” which features Spider-Man, our boy Harry of course, and a supervillain who gets defeated by a doorbell. (No really.)
So supervillain The Sorcerer – this was his only comic appearance ever by the way – decides to telepathically torment Spider-Man by giving him headaches. Peter collapses in bed for a bit… and when he wakes up Harry is crashing into his room and taking a shower in front of him. As you do.
Waitaminute, do these two sleep in the same room?!
That last panel there kinda indicates they do! So all Harry could afford for both of them was a one-bedroom apartment (with a shower next to the beds) huh?!
Okay, so actually the design for the apartment just changed a lot depending on the artist, here’s a little “tour” of what it’s supposed to look like from Amazing Spider-Man Annual #4 (1976)-
But all the same, if you want it to be it is totally canon that Peter and Harry sleep and shower in the same room together.
Moving back to the actual story…
Harry (who is drawn much more well-built in this than he usually is) takes both MJ and Gwen with him to go get Peter’s prescription from the doctor. (I wonder if he paid for it?)
But before he can get it back to him he sees Peter, hypnotized by The Sorcerer, driving towards the airport-
-and that’s all we see of Harry in the issue! None of this is ever mentioned again and the poor old Sorcerer will forever be a Z-list villain. It’s still a fun little story though.
Want to read this story? It’s collected in Amazing Spider-Man Masterworks Vol. 8.