It’s possible that it comes from Iseriel, which is (reportedly) the ancient Greek form of Jesharelah. Iseriel (reportedly) first appears written as such in the Septuagint, which is basically the first/earliest known Hebrew-to-Greek translation of the Old Testament. Jesharelah, which appears to be the original Hebrew, is said to mean “doubtful, upright towards God”. (source, source)
It also could be some kind of variant of [name_u]Israel[/name], too. No big explanation for that, it’s just that [name_m]Iser[/name] (the prefix-thing) always seems to come back around to root name [name_u]Israel[/name].
(Fun fact! [name_m]Iser[/name] can also mean “iron” or “ironworker”, thanks to its roots in German (spelling variation or nickname of occupational surname Eiser.) (source))
At the very least, I can say from the 30+ minutes I spent falling down a Google rabbit hole, it does not mean anything like “demonic ritual”, so I believe you are safe! 