post #1352613 post #1339981 post #1782909 post #2097756 post #4014148 post #4694436

Penetration tunneling is the penetration of something that is already wedged through another orifice, such that penetrating the "small" orifice that is sticking out indirectly ends up crossing the "large" orifice as well. Concretely, this can take the form of inserting a penetrable sextoy (like a tunnel plug, thus the name) in someone's anus, such that penetrating said sextoy would also indirectly count as anal penetration. A fleshlight gag that is penetrated while worn would also work. More often is the "living condom" variant, which is done through partial vore, by having the prey partially inside the pred, with the mouth or hips sticking out, and penetrating the prey's exposed orifices.

The "crossing the large orifice" part is not crucial. The point isn't to measure penis length or compare internal shots to see if it reaches that threshold.

Note that orifices with an inner and outer part, like the pussy/cervix pair or the genital slit/urethra pair don't get "re-counted", so a fellatio from both the inner and outer mouths of a xenomorph wouldn't qualify anymore than cervical penetration would count as recursive penetration. That doesn't mean that one person can't be both the "small" and "large" orifices, however, like with post #4014148 (fifth example) or post #4694436 (sixth example), which do that via self threading.

This tag is closely related to recursive penetration, with the important distinction that in the tunneling case, the "small" orifice is sticking out and is being penetrated directly, whereas in the recursive case, the "small" orifice is inside and the "large" orifice must be penetrated first to get to it. Penetration tunneling can transition into recursive penetration, like with post #2097756 (fourth example).

Related tags

• recursive_penetration: See previous paragraph.
• penetration_interlock: Another kind of "layered penetration", which usually involves a penis getting its urethra penetrated while it's inside something else.
• through_body/bulge_insertion: Use of bulges in ways that may involve penetrating someone else in a kind of train position, though this doesn't count as penetration_tunneling unless the non-penetrated end is also going in.

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