Raëlism is a belief system started by Raël, formerly Claud Vorhilon who claims aliens designed and created all life that is on Earth in alien laboratories. The alien creators, known as the Elohim are according to Vorhilon very keen on cloning and on free sexual experimentation, presumably Vorhilon likes both. The Elohim are due back on Earth in 2025 so it will be interesting to see how believers explain things if nothing happens then.
Incidentally believers are expected to give a tenth of their income to the organisation which looks potentially profitable for Vorhilon (Raël).
Naturally there is no independent evidence for the meetings Vorhilion (Raël) says he had with aliens or for what Vorhilion says aliens told him. Raëlism is about as reasonable or as unreasonable as other faith-based belief systems.