Definitely a female. I'd say you're probably spot on with Morgan as the size of her arms, hands and thighs seems fitting + they're trusted enough with one another to shoot this. I mean a bit of boob grabbing is nothing really crazy between two females and you never know what she might be wearing down under as it's always off screen or shot at an angle. For all I know Amouranth might actually be naked in some of these scenes but has her assistant wear one of her horse or pigeon masks so she can't really see 
