Jane Lane
J. Lane was a “known associate” of Jenny Everywhere in at least one incarnation, along with J. Lane, according to a wanted poster jointly put up for Jenny by a number of organisations who wished to bring her in for questioning. (PROSE: Wanted for Questioning)
Behind the scenes
Jane Lane is a character from the animated series Daria, being the best friend of Daria Morgendorffer (who is also referenced in Wanted for Questioning as D. Morgendorffer).
When and how Daria and Jane met Jenny Everwhere is unknown, but notably, there is precedent for Daria and Jane running into dimensional travelers. Although its canonicity is disputed by fans, the episode Depth Takes a Holiday showed them meeting anthropomorphic holidays and traveling briefly to another dimension.