it's important to note that the personalities and characteristics of K-pop idols can change over time, and new idols might have debuted since then. Additionally, the information I have might not be comprehensive or fully up-to-date.
That being said, there have been some K-pop idols who were known for being shy and introverted based on their public appearances and interactions. Here are a few examples:
Suga (Min Yoongi) from BTS: Suga has mentioned in interviews and variety shows that he's an introverted person who tends to be reserved in social situations.
Kai (Kim Jong-in) from EXO: Kai has talked about his introverted nature and how he can be shy, especially when meeting new people.
Taeyeon from Girls' Generation: Taeyeon has mentioned her introverted tendencies, saying that she prefers staying at home and having quiet time rather than going out to social events.
Wendy (Son Seung-wan) from Red Velvet: Wendy has shared that she's an introvert and that she used to struggle with shyness.
JB (Im Jae-bum) from GOT7: JB has mentioned that he is introverted and prefers spending time alone or with close friends.
Tzuyu (Chou Tzu-yu) from TWICE: Tzuyu has mentioned her introverted personality and how she needs time to recharge after being in crowded or social situations.
Baekhyun from EXO and SuperM: Baekhyun has talked about being shy and reserved, especially when he's meeting new people.
Please keep in mind that these are just a few examples, and there might be many more idols who are shy or introverted in the K-pop industry. Idols' personalities are diverse, and individuals can have different traits and characteristics even within the same group.