Hi! Yes, the Guesthouse is decent place. The setup's a bit different, as it's basically one apartment with a loft and only a few beds, really... but it's clean and orderly and the lady who owns/runs the place is very kind. I was actually just there for one night, as I got up really early to go diving in Sokcho the next morning... so I can't speak for activities or that sort of thing, but the ladies who were staying there at the time seemed to be enjoying themselves. As for Hongdae, it's perhaps the best place to be. I haven't explored it too much, but it's where Hongik University is and they supposedly have a swinging nightlife there... perhaps the best in the country... with great clubs, live music, etc. The subway is great, of course, so you're only ever a short ride away from all the other great places to check out in Seoul (temples, palaces, etc.). Hope this helps - Have a great time!!