There are several. The Afterschool DLC modifies the original dating system, the first date follows the original and basically acts kind of like how walking home does, uses that same background as well. From the second date on, you get to choose from a number of spots. There is also a new stat called intimacy, which determines which spots are unlocked and if the extra option for each is unlocked. The extra option starts an H scene in or near that location in an area you can't get to in the main game without being on a date in the corresponding location. Intimacy can be monitored on the class roster by hitting F4 and then switch info in the top right twice until the heart meter comes up. Dating and H scenes both increase this stat, but dating is the best way to do so. Then there is Darkness 1, 2, and 3, which add a janitor character to the first door on the left from the stairs on the third floor. You can bring any girl that is a lover, not a virgin, and that has a personality that is compatible to this door, which will have a purple hand icon. This starts an H scene where you allow the janitor to join in, but the only penetration other than in her mouth is done by you. He gets no anal or vaginal action. This is counted as a forced scene and you will take a large amount of damage to the affection stat, the curved meter that changes colors. This CAN result in her getting angry and breaking up with you as well, but it isn't guaranteed. Everything else just adds personalities and clothing options. The DLC personalities ARE NOT translated by Illusion through their Party release of the game, you will have to rely on the machine, so I would stay away from them until someone is nice enough to do a real translation job. None of this is automatic, you have to take a girl to the third floor yourslef for Darkness and you have to talk to a girl to get the date part going, though they may come to you and ask for a date, but no, no new story elements were added. Also, Afterschool is what gave us the ability for the player to join instead of just watching when catching a masturbation or lesbian scene. Bottom left, the blue button. It also added the ability for threesomes both through that ability to join lesbian H and through a mechanic where, if you start H with a second girl still in the room, if the girl has experience already and is your lover, there will be a pink button in the same spot as the blue one to join when peeping. The in game guide might explain it better, F5 key.