Lust Nightmare

Lust Nightmare (ラストナイトメア Rasuto naitomea) is the main villain and final boss of Lust Friend. She is the inner self of Mea and is the cause of the succubus world's future destruction.

Appearance
Lust Nightmare has long black hair with blue highlights, blue eyes, pale skin and extremely large breasts. She has curly black horns with blue tips, black wings with blue membranes, and a spaded tail. She wears a skimpy top and underwear, sleeves and thigh-length boots, all black with blue decorations. Overall, she looks like a succubus version of Mea.

Personality
Lust Nightmare is much more confident and aggressive than the quiet Mea. Despite being a succubus herself, she hates the succubi of the succubus world for ignoring Mea, to the point of repeatedly destroying the succubus world.

Along with Mea, Lust Nightmare has a complicated opinion of Magrut. She acknowledges him as their first friend, but doesn't trust him because she and Mea never had any friends and because of Magrut's efforts to befriend succubi. This leads her to try and trap him with her. However, she relents after Magrut proves his friendship with Mea, releasing Magrut and letting the succubus world be.

Background
Lust Nightmare was a succubus born from Mea's desire for friends.

One day, the girls around Mea proposed that she jump off a cliff to prove herself worthy of being their friend. Mea did so and was mortally wounded. Mea thought to herself that she should just give up and no longer have to suffer. However, Lust Nightmare called out to her. She introduced herself and asked Mea what she wanted. Mea replied that she wanted friends who would stay with her.

Lust Nightmare revived Mea and brought her to the succubus world. However, Mea still couldn't make any friends here as the succubi ignored her (seemingly because they could not perceive her at all). She became jealous of the succubi, who captured men and lived so happily with their friends.

Mea's loneliness led Lust Nightmare to repeatedly destroy the succubus world and then turn back time, despite knowing that this would not actually heal Mea's heart.

Lust Friend
When Magrut, another human, is brought into the succubus world, Lust Nightmare speaks to him (though her identity is not revealed at this stage). She tells him that it's impossible for humans and succubi to coexist, and this is world where he can only kill or be killed himself.

Lust Nightmare appears in person if, and only if, Magrut succeeds in befriending Empress. If this happens, Mea brings Magrut into a dark space and then transforms into Lust Nightmare. She explains her nature to him and states that she will now destroy the succubus world permanently. Finally, she mocks Magrut for his efforts to befriend succubi and declares her intention to keep him with her, until she and Mea disappear. In the resulting fight, Magrut talks to Lust Nightmare and eventually succeeds in befriending her. Lust Nightmare disappears, leaving only Mea behind.

If Magrut loses, Lust Nightmare proceeds to rape him. She reverses his time to make him regress into a child, intending to raise him up to be a proper friend for Mea.

Strategy
Lust Nightmare is a boss that you do not defeat conventionally, as the goal of this battle is to befriend her. This guide contains details of the Lust Nightmare battle, in the section titled "トゥルーエンド特殊ラストバトル攻略".

For this battle, you will begin with multiple new skills: Agree, Disagree, Prepare and Pray. The first is used to converse with Lust Nightmare, the second leads to an instant defeat, the third fills your Tension to the maximum and gives you an Agility buff, and Pray consumes 100 Tension to fully heal you. Note that you don't have Fess' blessing during this battle, so you'll lose if your Vigor reaches 0 even once.

Lust Nightmare will do nothing on her first turn. On her second turn, she uses Friendly Kiss, which reduces your Vigor to 1. Fortunately, she does nothing on her third turn, giving you an opportunity to heal. After the first three turns, Lust Nightmare will start using attacks that deal damage equal to 1/5 your maximum Vigor (though this can be reduced with Endure). You should therefore use Prepare whenever you're at 2/5 Vigor, then Pray on the next turn. This will reliably keep you alive while giving you the maximum number of turns free to befriend Lust Nightmare. If, at any point, you forget to use Prepare and have only 1/5 Vigor left, you can use a healing item to buy time to use Prepare and Pray.

To actually befriend Lust Nightmare, you need to use Agree four times (not necessarily on consecutive turns). You will then be presented with a choice of three options. Pick "Mea's past" and then "Mea's personality" (or the other way around, it doesn't matter). Don't pick "Mea's choice as it leads to an instant defeat. The next time you pick Agree, a fourth option will be added: "All of Mea".

The Agree and Disagree skills will now disappear, being replaced with Comfort, Listen and Talk. Use Talk and then pick "Talk about yourself" twice. Don't pick "Talk about your friends", it leads to an instant defeat. After this, use Listen twice. Finally, use Comfort twice. Two options will appear, and it doesn't matter which you pick as both lead to the Friend Flag.

When you obtain the Friend Flag, all of the new skills will disappear, most of your existing skills will be greyed-out, and Lust Nightmare will stop attacking. Use Befriend, and Lust Nightmare will be replaced with Mea. Use Embrace three times to end the battle.