(CNN) -- The co-founder of Rap Genius, an online-annotation website, has been fired after marking up the 137-page manifesto of California killer Elliot Rodger with comments that are being called tasteless and creepy. Mahbod Moghadam used his site, which lets users post notes interpreting rap and hip-hop lyrics, to comment on Rodger's exhaustive autobiography, which includes his reasons for killing six people in Santa Barbara, California, on Friday before apparently turning a gun on himself. In more than one note, Moghadam called Rodger's writing "beautiful," and in another he speculated on the attractiveness of Rodger's sister. In a journal and in a video posted online, Rodger had expressed frustrations about not finding women to date and resentment toward couples who kissed in front of him.
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Rap Genius co-founder made insensitive comments about killer's manifesto
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Mahbod Moghadam called Elliot Rodger's writing "beautiful"
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He also speculated on the sex appeal of Rodger's sister
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Rap Genius CEO: "I cannot let him jeopardize the Rap Genius mission"
As is frequently the case in today's digital world, the social-media backlash against @placeholder's comments was fast and brutal.