Starting with the Japanese demon, Kagekao!
How I would handle it:
Me: *wakes up to glass shattering in the kitchen* I better not have summoned a character from any of my favorite fandoms...
Me: *gets out of bed and walks to the kitchen*
Me: This place looks clean... Where's all the glass?
???: こんにちは。遊びたい？ (Hello there. Wanna play?)
Me: Oh hell naw! Who summoned Kagekao?!
Kagekao: 遊びたい？私はあなたが遊ぶことを望む！(Wanna play? I want you to play!)
Me: *sighs* Desperate times call for desperate measures...
Me: *turns around* お前は一体誰だ？！(Who the hell are you?!)
Kagekao: *tilts his head* あなたは日本語を話しますか？(You speak Japanese?)
Me: *nods my head* はい。あなたは誰ですか、あなたは私の家で何をしていますか？(Yes. Who are you, and what the fuck are you doing in my house?)
Kagekao: ケーケケ！私は話すためにここにいる。(Ke-ke-ke!  I'm here to talk.)
Me: ええ、その通り。私はスサノオノミコトの子孫です。なぜあなたはここにいるのですか？ (Yeah, right. And I'm the descendant of Susanoo-no-mikoto.  Why are you here?)
Kagekao: 私はあなたに警告するためにここに来た。(I came here to warn you.)
Me: 何について私に警告しますか？ (Warn me about what?)
Kagekao: Jeffrey Woods、Jeff the Killerに気をつけてください。(Beware of Jeffrey Woods, or Jeff the Killer, as you may call him.)
Me: Fuck! Now I'm definitely dead!