Viewers saw Zoe having a lesbian encounter with Sarah (Loui Batley) in late night spinoff Hollyoaks Later last year, but they went on to dismiss the experience as a drunken mistake.
Discussing the current state of the pair's relationship in an interview with DS, Lister explained: "I don't think they do have feelings for each other in that way. Last year happened and Zoe put it down to history and experience - one of those things that teenagers get up to occasionally and she was quite happy to leave it there.
"They've got through a lot and their relationship is really quite special. There's a lot of love there but Zoe's not got anything sexual for Sarah - it's purely a deep friendship."
Meanwhile, Batley said: "I think that for Sarah, Zoe's the best friend she's ever had - a lot of people in her life have let her down but Zoe's her rock. Even though they've had their fall-outs, she's always been there for her and she loves her as a friend.
"I think Zoe feels the same. But for Sarah it's something more - she completely relies on her and that turns into love for her as well."
This year's Later series will see either Zoe or Sarah killed off in a skydiving tragedy. The dramatic scenes will air in tonight's instalment.
Hollyoaks Later continues at 9pm tonight on E4.
> Click here to read our full interview with Zoë Lister and Loui Batley