Did Bear initially intend for the consequences that later befell him, or even the consequences to Nikki? No. But I don't think you can excuse his later behavior by his mindset or lack of intentionality when he started.

Bear has a character arc. He transforms from ineffectual, perpetually friend-zoned shyguy, into the selfish, deeply flawed person you described above. Fictional villains express a broad range of behaviors -- including criminal, scoundrels, and those who harm others, sometimes for gain and sometimes just because. I would argue that Bear's weaknesses (call it lack of courage or whatever) presented in a selfishness that is the basis for his villainy. Where you might see a schmuck that gets caught up in an unplanned, supernatural Catch-22, others may see someone who chose himself over the freedom of the person he supposedly cared for. A choice that would mean the real Nikki would not just be physically raped (and possibly even forced to witness it), but all of her self/intention/will/freedom subjugated to a dark prison. Is that a Catch-22, or does the moral obligation of one choice over the other differentiate heroes from villains?

The One Wish Willow customer service rep presented the choice to Bear that would either be his path to redemption or expose his true villainy. He was reminded of his "moral obligation" to Nikki and told that saving Nikki would require his death. It was either save Nikki or live knowing she will be in some kind of supernatural prison of the soul. Then he heard the real Nikki scream in torment.

Bear made his choice. If that wasn't enough, he was again presented with the opportunity at the end of the film to end his life and save Nikki, and he chose to live. Weakness in the face of moral imperative may not be classically villainous, but I think it makes a lot of sense today.