Jess is very gentle and very pastoral.
She has known Mike for a very long time, and she knows how important the Lady Jane is to him, and how he has always felt about her.
It is Jess who takes Jane in at the time she arrives in the 21st century, and in the month Jane spends with her, Jess comes to care for Jane very much.
She is the Mother that Jane never had.
It is Jess who sets Jane up in her own apartment and buys her everything she needs to live comfortably in the 21st Century. It is never really explained, but just inferred, that Jess is rather wealthy.
