That happiness which arises from the contact of senses and sense-objects, which seems like nectar at first but is like poison in the end — that is called rajasic.

The sattvic happiness is exactly inverted in its temporal structure: it is nectar at the end. Rajasic happiness — the happiness of sensory pleasure, of getting what we desire — is the reverse: nectar at first, poison at the end. This is one of the most practically important teachings in the Gita. Every person who has experienced the pattern of desire, gratification, and the subsequent emptiness or craving knows this structure. The pleasure is real; so is the subsequent suffering. The rajasic happiness arises from viṣayendriya-saṃyoga — the contact of senses with their objects — and it is inherently impermanent because the contact cannot be maintained and the hunger returns stronger than before.