Bliss out
Definition 1 of 1
Pro Tip 1/3Slang Usage
Considered slang, used in casual situations among friends or in relaxed environments, not in formal settings. 
Let's hang out at the beach and just bliss out.
Pro Tip 2/3Positive Vibes
Carries a positive emotional charge, suggesting deep contentment or pleasure. 
After the yoga session, I completely blissed out.
Pro Tip 3/3Activity Specific
Often used with an activity, like listening to music or enjoying nature, which provides the pleasure. 
I could bliss out to classical music for hours.