(adj.) someone, esp. male in early- to mid-adulthood, who is lanky, gangly and physically awkward

Voluntarily Celibate.
A person who chooses to be celibate. Can be for any given amount of time, for a short period or for their entire life. Can be for religious reasons or not.

related: incel

(adj.)used to describe someone who is very creepy and sleazy

someone being awkward, tall, and skinny.

Extremely tall and skinny

Having everything to with being creepy, overly touchy, unwelcome in advances or presence, may include, but is not limited to, those who are heavily intoxicated.
Probably derived from the use of lurky and creepy combined, thus lur-py.

Many variations exist all with the same general implications. One can lurp, be a lurp, a lurpster, a lurp show, be lurpy, be lurptastic, or do something lurpily.

To make unwelcomed advances, often while heavily intoxicated; becoming overly friendly and forward, bordering being creepy