AToHA, Portal Shenanigans: A Collision of Worlds (Patreon)

It had been some time since Ciri had enjoyed a nice reprieve. The last time had been a brief visit to Nymphia's realm, where she first met the goddess. Ciri had not expected to hear from Nymphia or Syla after her visit and was surprised when she got the request to return. Upon arriving at the goddess's realm, Ciri was warmly greeted and informed about an elf mage, Elliandri, and her search for other planes and worlds. Nymphia and Syla both vouched for the mage, convincing Ciri that meeting her could be beneficial. Word was sent ahead to Elliandri before Ciri was sent on her way to visit the mage. Their meeting proved worthwhile as the two went from sharing introductions to removing their clothes, their bodies erotically intertwined as they engaged in intercourse. By the end, Ciri lay exhausted, her head in Elliandri's lap as she toyed with the mage's phallus, thoroughly satisfied by the elf's efforts. As Ciri prepared to leave, she informed Elliandri that she would see about convincing some mages from her world to visit for them to exchange knowledge (and maybe some other, naughtier things).

I've decided to refer to these crossover events as "Portal Shenanigans" or "PS" as they will act as small side story events in universe.