From the Super Mario Wiki
Professor Frankly is Goombella'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 the only known Goombas to have square teeth rather than pointed teeth, with 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 and knock him unconscious - Doopliss takes the guise of the professor in order to trick Mario into opening the Thousand-Year Door, to allow Grodus into the Palace of Shadow. 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.
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