It's completely linear, there are some options but they don't matter much since from what I've seen on forums, most people who play this are looking for a linear and interesting story and that's exactly what this game does, it would be very fucked if there were options to reject the main girls or in the end breaking with them or things like bad endings, that's why I'm in favor of most people looking for a linear, loving, interesting and emblematic story, after all it is a 100% harem game.