youtube.com/watch?v=sdLWSntHYb4 The 3 characters and another light-novel based anime role they were in: Ayame=Jamie Marchi (Rias in DxD) Tanukichi=Josh Grelle (Shido in "Date A Live") Anna=Monica Rial (Houki in "Infinite Stratos")
I'll spare you from linking the youtube video but the random google search i went for after reading your topic title landed me on a video called 'Vegan Semen Protein Cookies'.