Theresa Lachner is a journalist, a systemic sex therapist, and the founder of the largest German-speaking sex blog, LVSTPRINZIP (pleasure principle), a podcast by the same name, and she is the author of the book LVSTPRINZIP. 

Lachner has been writing for media outlets such as Business Punk, NEON, Spiegel Online, ZEIT, and several women's magazines. What's more, she is the editor-in-chief of SCHRIFT X. As a systemic sex therapist she is working with personal consultations as well as with couples, and with companies and brands, from health insurance companies to advertising agencies and coffee shops, to foster a more liberated approach to sexuality in society.