Demonen forsvinner.

Because -en is the definite article attached to the noun.

• demon = a demon
• demonen = the demon

In Norwegian, the definite article is usually added to the end of the noun instead of being a separate word in front, as in English.

So:

• Demonen forsvinner. = The demon disappears.

Demon is usually a common gender noun in Norwegian. Common gender nouns typically take -en in the singular definite form.

A common pattern is:

• indefinite singular: en demon
• definite singular: demonen

So -en here marks the demon.

Forsvinner is the present tense of the verb forsvinne, which means to disappear or to vanish.

So:

• å forsvinne = to disappear
• forsvinner = disappears / is disappearing

Depending on context, English might translate it as either:

• The demon disappears
• The demon is disappearing

In Norwegian, many verbs form the present tense with -er.

Here:

• infinitive: forsvinne
• present tense: forsvinner

This is very normal in Norwegian. The -er ending often corresponds to English disappears, runs, speaks, and so on.

No. In Norwegian, verbs usually do not change according to the subject in the present tense.

So you get:

• Jeg forsvinner = I disappear / am disappearing
• Du forsvinner = you disappear
• Demonen forsvinner = the demon disappears

The verb form forsvinner stays the same.

This is the normal Norwegian subject + verb order for a simple main clause.

• Demonen = subject
• forsvinner = verb

So it works just like basic English word order:

• The demon disappears.

Norwegian often uses this straightforward order in ordinary statements.

Yes. Norwegian present tense often covers both:

• The demon disappears
• The demon is disappearing

The exact meaning depends on context.

Unlike English, Norwegian does not always need a separate progressive form like is disappearing. Very often, the simple present is enough.

You would say:

En demon forsvinner.

Compare:

• En demon forsvinner. = A demon disappears.
• Demonen forsvinner. = The demon disappears.

So the main difference is:

• en demon = indefinite
• demonen = definite

A learner-friendly approximation is:

deh-moo-nen

A few useful points:

• the final -en is pronounced as part of the word, not as a separate word
• the stress is usually on the second syllable of demon
• Norwegian pronunciation varies somewhat by dialect

If you are learning Bokmål pronunciation, listening to native audio is the best way to get the vowel sounds right.

Sometimes, yes. Norwegian present tense can sometimes refer to the near future if the context makes that clear.

So Demonen forsvinner could mean something like The demon is disappearing now, or in the right context, The demon disappears / will disappear.

But if you want to make the future meaning clearer, Norwegian often adds time words or uses another structure, for example:

• Demonen forsvinner snart. = The demon will disappear soon.

Yes: its present tense stem changes a little.

• infinitive: forsvinne
• present: forsvinner

You do not get forsvinneer. The verb changes naturally to forsvinner.

This is just something to learn as part of the verb’s pattern. It is a very common and useful verb in Norwegian.