If a normal girl saw a book like that, she'd be totally turned off!
Literal
That-kind-of book saw [conditional-たら] normal girl [topic-は] pull-back [emphatic-もんな]!
フツー is the katakana spelling of 普通 'normal,' used for casual emphasis. 引く in its modern slang sense means 'to be turned off / to cringe.' もんな is a masculine/casual emphatic sentence-ender (もの + な). The sentence has the tone of a guy warning another about showing inappropriate material.