While
higher spiritual education is important for pastors and Bible teachers, I'm not sure that getting a demon degree is necessary. For one, there are very few Bible colleges or seminaries that have degrees in demonology.
There are some options, however. BIOLA has a directory listing their experts on spiritual warfare. Wagner University does offer an MA in "Spiritual Healing, Deliverance, and Warfare" (which includes a course on "Cleansing Stream Method"). Even my own school, Dallas Theological Seminary, has a class on angelology, although it's combined with anthropology and hamartiology.
It is true that spiritual warfare is real and serious. We here at NotQuestions just don't know if it's necessary—or wise—to get an entire degree in demons. It's better to know the truth than the lies. If you're very driven, you've had Greek and Hebrew, you have a Master of Theology degree, and you have a ridiculous amount of time on your hands, you can always get a Doctorate of Ministry. Whether you're a pastor, a scholar, or a writer for a parachurch ministry, a DMin degree would round out your education.