There's not all that much tsun in Tewi's dere. No, I think it's actually closer to two yandere like KuroBaraHime said, only with different types of yan.
Both yandere, one is outwardly aggressive and views others and their potential love interest as the ones that wrongs them most, the other is desperate clingy internally depreciative and sees themselves as the ones who are lacking. One externalizes the threat to the relationship, the other internalizes them. Both are overbearing, overprotective, prone to emotional outbursts,
Eh, wai...Well whatever.It's not like I'm a demon.Romantic, huh...Chen, have you ever loved someone?Ahaha,○Keine vs Tewi×
[Five Seconds, French Kiss] Why? Why? Why? Why?
Why? Why? Why? Why?
Why? Why? Why? Why?
Why? Why? Why? Why?
Why? Why? Why? Why?
Why? Why? Why? Why?
Why? Why? Why? Why?Stupid person A here!!Eh?Kyahoo!You've got it wrong Chen... I don't think of anyone but you. I don't look at anyone but you. I don't care about anyone but you. Nothing has any worth but you. Nothing has any meaning but you. So don't be angry. Don't be sad. Don't hate me. If you hated me I couldn't live anymore. If you hated me there would be no point in living. I'm sorry. Forgive me. I'm sorry. I'm sorry. I'm sorry. I'm sorry. I'm sorry. I'm sorry. I'm sorry.I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.
I'm sorry. I'm sorry.What is this, Teh-chan...? Is that how you think of me? Didn't I say you couldn't listen to anyone but me? Didn't I say you couldn't look at anyone but me? Didn't I say you couldn't speak to anyone but me? Didn't I say you couldn't think of anyone but me? Why can't you do such simple things for me? Am I the strange one? Am I the wrong one? Answer me, answer me. Why? Well, why? Why? Why? Why? Why?Alright, let meow do this...I was wondering if even someone like you who doesn't possess a human heart would make the face of a lusty bitch when in front of someone she likes.You aren't?Anyway, let's see what'll happen if we bring Keine-sensei here.Hmm? You're making it sound like I was born from and have been living in the darkness.Now take it easy Chen. You should display to the stupid masses that you're really an angel.Did I kill your parents or something?Chen, you're hitting Teh-chan's switch again.HahahaMutterI'm getting excited despite the situation.