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Yes, it is safe to rinse your mouth with listerine and to shower. There has been much myth about whether listerine or other mouthwashes helps or hurts, but there is no evidence that it makes a difference. Part of the reason that the myth has perpetuated is that it is difficult to perform a study to definitively prove that it does not alter the rate of transmission. But the current expert consensus is that there does not appear to be any risk or benefit to using mouthwash after the fact.
Of the actions that you performed, there is some risk associated with the protected insertive anal sex and the unprotected oral sex, although the risk is lower than what most people think is present. The risk is about 0.01% - 0.06%, if the partner was HIV positive. If the partner was of unknown HIV status, then your actual risk would be lower, by a factor that is the prevalence of HIV in your community.
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