composed, contented
憪 centers on a calm, satisfied state of mind: being composed and contented, without agitation or desire.
憪 combines the heart radical 忄 with 閒, which likely contributes the sound and the idea of leisure or calm. The exact historical development is uncertain.
The heart radical 忄 beside 閒 (which suggests leisure or a gap) gives the image of a heart with space and time to rest: a composed, contented mind.
For カン, picture a calm person sitting by a can of tea, completely content: can -> カン, and the heart is at ease.