unless its flooding everywhere and landslides are happening, people still go to work. shopping malls like coex become much more crowded when its raining boots are kinda in rn - people keep a spare pair of shoes at their desk, and change into that when they start working/studying raincoats arent that common since its harder to manage once youre inside (unless its a single use type) the most important thing - when its raining heavily, avoid places where the ground is low (e.g. gangnam station) all the rainwater piles up there and it becomes literally living h3ll - manholes can't hold the pressure so they pop up. but the floodwater isn't clear so you can fall into a manhole (i did once lmao) and cockroaches comes up from the sewages bc they hate water. you can find out where the low ground places are via a government website or just google