I have some questions about special rules of the Ghoul and Minstrel.

The Ghoul and the Minstrel (basic game characters) both have the option to get enemies from adventure cards as a kind of followers. The Ghoul can revive any enemies killed in battle, the Minstrel can charm animal type enemies. The character cards say they join "as followers" (Minstrel)/kept "as followers" (Ghoul).

However, as the cards are adventure cards, are those creatures really considered followers for all rules and cards that mention followers?

If no, in which cases are those creatures treated as followers?

Are they simply discarded if a character turns into a toad or dies (or in similar events)?

Let me take a shot at answering this - and if I'm wrong, some of the more experienced players will chime in, I'm sure.

As long as they are followers of the Ghoul (raised enemies) and Minstril (charmed animals), they follow all of the rules for followers. This includes being targeted by spells or effects that target followers. However, once they are no longer followers of those characters, they are treated as normal adventure cards, and thus, enemies.

For example, if the Minstril is turned into a Toad, all of his followers are dropped - including his charmed animals. If the Minstril later moves back onto that space, or another character lands on that space, all of those animals are now encountered just like any other card.

However, I think I do remember reading that you cannot steal a follower of this sort if you cannot normally take them as followers - for example, the Sorcoress cannot beguile the Minstril's animal followers because she cannot take animals as followers.

The answer from Katana_one is correct