Red Love Heart Bomb.
This is atriggered particle effect and will need the latets client to work correctly.
Just put it in your rooms and when ever you type in the trigger word: love , the effect will start filling your room with red love hearts, thye will dissappear after about 2 minutes, when you can trigger again. Big particles like this tend to lag a room, so by having triggers it allows you to contol when these things run, great for public rooms as you can trigger once people have loaded into the room.