Mister Fantastic
From Tardis Wiki, the free Doctor Who reference
Mister Fantastic was the superhero alias of Reed Richards. He was a member of the Fantastic Four, the husband of Sue Richards, and the father of Franklin Richards. (COMIC: Clobberin' Time!)
References
When Fitz Kreiner's arm elongated, it reminded him of the "bendy bloke" of the Fantastic Four. (PROSE: The Book of the Still)
Bill Potts asked jokingly if the Twelfth Doctor had stretchy arms like Mister Fantastic. (TV: Smile)