If a partner were to have sex and express a deep desire and mad love for one another they would end up conjoined.

Some sex positions are outright avoided and in some cases became taboo but for the rest it was up to the choices of the pair. The conjointment process usually includes internal organs rearranged to ensure both live long in the end and usually it could end with an organ, esp sex organ, merged.

>Couple deep in a missionary, woman about to reach a climax, now staring longingly at her partner with deep love for him
>After a big thrust, both started melting into one another, both finding their sex organs melting into one, the woman feeling something stir at the pit of her stomach, moving up towards her inside her chest, then neck, before vomiting out cum.