Professor Frankly is Goombella's and Kolorado's old teacher at U Goom in the game Paper Mario: The Thousand-Year Door. He wears thick glasses, as indicated by the swirls in the glass, which is a common motif used in Japanese media (other Mario characters with swirled glasses include Professor Elvin Gadd, Iggy Koopa, Fawful, and Francis). Professor Frankly is one of two known Goombas to have square teeth rather than pointed teeth, the other being Goombario. Frankly's name is derived from the qualifier "frankly", a word commonly used by intellectuals to emphasize the truthfulness of what they are about to say.
After Mario and team visit the Thousand-Year Door, he tells Mario and his teammates where one of the Crystal Stars is. In addition, tattle log entries that the player may have missed can be found in Frankly's bin. The good Professor consults with Mario and Goombella at various points during their quest, and helps them with hints on where to go next. On the back shelf of his house, a miniature version of the head-shaped rocks at the entrance to Pirate's Grotto can be seen, as well as spherical objects bearing the Sun, Moon, Star, and Puni designs seen in the Great Tree.
After Mario and co. obtain the final Crystal Star from the X-Naut Fortress, the Shadow Sirens abduct Frankly, knock him unconscious, and then locked him up in a closet. Doopliss takes the guise of the professor in order to trick Mario into opening the Thousand-Year Door so Grodus can enter the Palace of Shadow. Frankly later escapes and gives chase into the palace. After the Shadow Queen is awakened and possesses Princess Peach, the real Frankly is seen in one of the palace's darkened rooms, distressed at the thought of her revival. Following the defeat of the final boss, he reunites with Mario and co. and reveals his discovery of a large treasure chest containing the true treasure. Visiting him post-game reveals the contents of this chest to be a seemingly insignificant Dried Shroom. However, Frankly is excited nonetheless by it, as it proves that residents of the ancient city ate Mushrooms.
That's Professor Frankly, head of the archaeology department at U Goom. He's researching the legendary treasure here. I totally respect him. You know the famous Professor Kolorado? He was a student of Frankly's!
Professor Frankly breaks the fourth wall just before Chapter 5 by telling the player, the "person in front of the TV" to listen carefully about what he has to say about The Thousand-Year Door. Mario's current partner then comments about that, but Frankly tells them to disregard it. Lord Crump (under the alias of Four Eyes) also breaks the Fourth Wall during this chapter.
Likely due to an oversight, if the player uses the phone booth in Glitzville after Professor Frankly's abducted, it is still possible to receive a call, supposedly from Frankly himself, warning Mario to be careful in his travels.