Egoma is an annual. Although it looks a lot like green shiso, its leaves are firmer and generally rounder.
In South Korea, the leaves are typically eaten with grilled meat or used as an ingredient in kimchi. In Japan it is the seeds that are largely used.
A fantastic source of plant-based Omega-3 fatty acids - Perilla oil can be derived from the seeds of this plant. For best absorption, it is best to use the leaves/seeds/oil without heating them up e.g as a topping for a salad.