Doki Heika Banzai!
Most mods install on top of a fresh copy of DDLC, free from ddlc.moe. Follow the author's instructions, and keep a clean copy of the game.
About this mod
This is the project I've worked on for the last couple weeks. It's a comedy set in WW2 Imperial Japan and it's pretty short! I can't really reveal much of the plot without giving away too much, but I can tell you that the protagonist and the four girls are going to war in this one and whacky adventures are ensured! The mod is a bit NSFW.