Don’t do that.
Usually the wet dreams are not mortally sinful as we have not control over dreams.
However, if you purposefully do things in dreams that means you are using your will.
Instead, pray the Rosary, and don’t try to “release” but channel the energy spent in arousal to something else like a good book, prayer, exercise, etc.
Sounds like a fine line you may be crossing. If prior to sleep, you set yourself up for this in some was, you may, may be sinning. Talk to your confessor to be sure.
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