This is the rarest pairing in the chart, and you do not have it. What you may have is the transit, and that is heavy enough.
What it looks like in a life
Neptune and Pluto stood opposite each other around 1645, Neptune in Capricorn against Pluto in Cancer. Everyone born in that window shared it. The next opposition falls around 2140. Their cycle runs close to 492 years, so no living person carries this natally and none will. If your report shows it, you are reading a transit: Pluto opposing your natal Neptune or Neptune opposing your natal Pluto. Each happens once in a life at most. It runs for years and it feels like this. Something you have been dissolving into, a substance, a belief, a person, a version of yourself, gets held up directly against something that is ending and will not be argued with.
The gift
An opposition makes both sides visible by putting them across the table from each other. You cannot drift, because something keeps ending, and you cannot simply destroy, because something keeps asking what the mercy is. Held long enough, that produces a person who can watch a life dismantle itself and stay compassionate about it. Nothing else in the chart teaches that at this depth.
The friction
Two opposed forces take turns running a life. A period of escape and blur, then a period of grim control and cutting away, each answering the last. The swing can run for years. The escape looks like peace and the destruction looks like honesty, and neither is, until the middle ground gets built on purpose.
The esoteric layer
Neither planet was known to the ancient astrologers, so nothing here belongs to that tradition. The esoteric framing is Bailey and modern. The opposition is the number two, and esoteric astrology reads it as full moon logic: illumination through the other, the pair held in tension until a third reconciling point is found. Bailey counts Neptune sacred and sixth ray, devotion whose work is the dissolution of the separate self, and Pluto non-sacred and first ray in its destroyer function, ending what the soul has finished with. Opposed, they are surrender and death staring at each other.
Where this goes
If this is transiting your chart, the houses it crosses say what is dissolving and what is dying. That is the exact material a therapeutic astrology session works with.
Related
See it in your own chart
Cast your chart free and read this placement next to everything else you carry.