oral historian
A person who either researches the early beginnings of the practice of fellatio. or documents the quantity/quality of lips/tongue-pleasuring experienced/given by a certain person or group.
As much fooling around as Wee-wee Willie Wankie and Monica Blewinsky engaged in --- both with each other and separately with other folks in the D.C. area --- an oral historian could almost make an entire lifelong career out of putting down on paper the lurid/sordid details of the various trysts of just these two individuals alone!