What is Reiju? How does it relate to Reiki attunement?

One very Reiki approach is to think of them as two different ways to tune a radio to your favorite station. 

Eastern Reiju is like gently cleaning the radio antenna over and over so the signal naturally gets clearer and clearer. It translates to a "spiritual blessing."  A Shinpiden (Reiki Master) gives it to you repeatedly—sometimes every week. There is no switch to flip; it is a quiet, ongoing gift that helps your own natural connection grow deeper and deeper over time.

Western Attunement is like a master technician turning the dial once exactly to the right station. The Western Reiki Master Teacher does a special ceremony that is believed to operate like flipping an internal switch so that the student is ready to "channel" Reiki immediately. It is an  event that occurs once to twice in each Level of Reiki training (eg R1, R2 and R3). Some Reiki Associations stipulate the number of attunements at each level of Reiki training. Western Attunements use a detailed ritual sequence often integrating special symbols and may also include various new age concepts added onto the older original Japanese Reiki. 

In summary, a Shinpiden (Reiki Master) trained in Eastern Reiki is able to offer Reiju. The Reiju recipient (s) dose not have to be in training, or undergoing training to receive Reiju.  As mentioned Reiju is offered to all who attend Eastern Reiki meetings and is also used to provide a very special Reiki treatment. Owen offers Reiju in this sense. Currently, he does not offer western attunement.