Ikeda's Wedding Dungeon Crawl Who: Shadow Kiriko and Exploration Team. What: Dungeon crawling. Where: Ikeda's Wedding Dungeon Crawl. When: June 14/15 Why: Dungeon crawling chat supplementals!
The entrance to the dungeon takes the form of a small, Western-style chapel, with sleek, towering glass buildings visible in the distance. The closest seems to be a hotel, but an inaccessible skyline lined with modern office buildings and interesting architecture belonging to no particular cityscape is visible as well.
ETA: Dungeon Summary for those who have missed all or parts of it and don't want to pick through the chat.
Also note that Yuuto and Masami are chained together, and Emi isn't chained to anyone at all.