Devas

On Page One Hundred and Four, Sayadaw instructs on developing lovingkindness toward these 22 categories and to 'actually see' each of these persons occupying a whole category.  This reminds me of various Tibetan practices.

Some persons think that the Tibetan Buddhists were the first to expound on the six realms of Gods, Asuras, Humans, Animals, Hungry Ghosts and Hell Beings.   In Theravada Buddhism, there are the same, only five total as Asuras and Gods are combined:

Here's a brief explanation