by using somthing that they would like a place to have, for example for a costumer to come and rent a apartment you should add free services like cabel or internet
dont is my answer. if they are all ready going out with someone it's because they really like them and to break them apart would be mean. but you could wait untill they break up, and then wait a week...
Scenically, there is no such thing as "aliens" because in our solar system none of the planets have life. Mars have ice so there may have a chance of life. So scientifically aliens don't go to place...