If you're friendly and outgoing, you're genial. You can be a genial host or a genial guest.
This is mainly a word for pleasant kindness. Besides people or animals, climates and weather can be genial, which means they too are warm and sunny — good for growing things. In older literature, genial might have something to do with marriage and family, and sometimes brilliance, as in genius. Those uses are very rare nowadays, as is the sense of genial as having to do with the jaw. These days, warmth and friendliness are the main meanings.