plump, voluptuous, beautiful
豔 centers on a lush, full-bodied beauty: plumpness, voluptuousness, and an attractive, flourishing appearance. The meanings all point to a rich, sensuous attractiveness.
豔 combines 豐 (abundant, lush) with 盍, which likely contributes a phonetic element. The character expresses the idea of rich, full beauty through the sense of abundance.
The left side 豐 suggests abundance and richness, like a bountiful harvest. The right side 盍 adds a sense of covering or fullness. Together, they paint a picture of overflowing, voluptuous beauty.
For エン, imagine an enchanting, plump beauty: enchanting -> エン, and her voluptuous charm fills the scene.