A [[couple]] that switches between dominant and submissive roles, sexual or not. 
This can involve any sexual act and does not require [[anal]] or vaginal [[sex]], but it is the most common depiction.

Especially in [[yaoi]], a reversible couple will top and bottom for one another. [[Hetero]] and [[yuri]] couples may make use of a [[strap-on]] to achieve penetration. 

Different roles for each character can appear in:- 

* Single image: post #6739606, post #6138695
* In a related image: post #6755546 with post #6755554
* Non-sexual depiction: post #6657405, post #6534375 with post #6537710, post #6947169 with post #6947170
* Implied [[reversible couple]]: post #6573362, post #6921017

This tag does not apply to images where a character tops and bottoms with different individuals.

h4. See also 

* [[muscular uke]]
* [[top (sexual preference)]]
* [[bottom (sexual preference)]]
* [[role reversal]]
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