i-adjective
sentimental; mushy; saccharine
Describes overly emotional, sweet, or cloying behavior, words, or atmosphere, often with a negative or mocking tone.
彼の甘ったるいセリフには、みんなが引いてしまった。
Everyone was put off by his mushy lines.
That movie was such a saccharine love story that I couldn't watch it.
i-adjective
Used for food or drink that is excessively sweet in an unpleasant way.
このケーキは甘ったるくて、一口で十分だ。
This cake is sickly-sweet; one bite is enough.
甘ったるいジュースより、お茶のほうが好きだ。
I prefer tea to sugary juice.