I believe there is tissue that gives sexual enjoyment but I know that not all women have them (or feel them) so that is probably why the existence of one is debatable. It's up to the woman to say whether she finds something enjoyable and not all women feel that. Maybe it's an internal extension of the clitoris but not all women clitoris extend far enough for them to feel it inside. It could also be a similar structure to the male prostate such as the paraurethral glands that explains the ‘squirting’ some women say they experience. If you tried finding something anteriorly that feels ‘good’ to touch then you may call that the G spot, if you cannot then you probably don’t have one (or feel one).