Copious - abundant; plentiful
Tenacious - tough; stubborn; not letting go
Surreptitious - done or acting in a secret, sly manner
Voracious - an insatiable appetite for an activity or pursuit; eager to consume great amounts of food
Officious - ready to serve; eager in offering unwanted services or advice
Spurious - not genuine; false
Onerous - troublesome or oppressive; burdensome
Gregarious - seeking and enjoying the company of others; sociable
Pious - devout or virtuous; holy
Scrupulous - careful of small details; honest; conscientious