How do we want to do the draining? Can absorb a power point per round/minute/?, Will save negates? Victim doesn't know about it?
Yes something like that.
We can also turn to the SRD Psionic Monsters for some inspiration. For example, the Brain Mole uses
power leech and Power Conversion.
Power Conversion (Su): When a brain mole drains a power point by means of its
power leech power, it immediately heals 1 hit point. If it is already at full normal hit points, it instead gains psionic sustenance sufficient to supply its need for nourishment for 24 hours.
Power Leech
Telepathy (Compulsion) [Mind-Affecting]
Level: Psion/wilder 4
Display: Visual; see text
Manifesting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: Any psionic creature
Duration: Concentration, up to 1 round/level; see text
Saving Throw: Will negates
Power Resistance: Yes
Power Points: 7
Your brow erupts with an arc of crackling dark energy that connects with your foe, draining it of 1d6 power points and adding 1 of those points to your reserve (unless that gain would cause you to exceed your maximum).
The drain continues in each round you maintain concentration while the subject of the drain remains in range. If the subject is drained to 0 power points, this power ends.
Concentrating to maintain power leech is a full-round action (you can take no other actions aside from a 5-foot step) instead of a standard action.