Merula doesn't pop up because she is busy with her own tasks and responsibilities. She may be focused on her studies, practicing her magical skills, or working on her own personal goals. Additionally, she may not feel the need to constantly be in the spotlight or interact with others, preferring to keep to herself. Ultimately, Merula's absence may be a result of her independent and determined nature. **

Pop-up notifications are brief messages that appear on a user's screen, typically on a computer or mobile device, to provide information or alerts about a specific event or update. These notifications can come from various sources such as apps, websites, or operating systems, and are designed to grab the user's attention quickly. Pop-up notifications are commonly used to inform users about new messages, reminders, software updates, or other important information in real-time. **

"Pop up" typically refers to something that suddenly appears or appears unexpectedly. It can be used to describe a sudden appearance of something physical, such as a pop-up book or a pop-up store, or it can refer to something that appears on a computer screen, such as a pop-up ad or notification. In general, "pop up" conveys the idea of something appearing quickly and often unexpectedly. **

English Pop Art and American Pop Art both emerged in the 1950s and 1960s as a reaction against traditional art forms, but they have some key differences. English Pop Art, led by artists like Richard Hamilton and Peter Blake, focused more on consumer culture and mass media, often incorporating elements of British popular culture. American Pop Art, on the other hand, led by artists like Andy Warhol and Roy Lichtenstein, placed a greater emphasis on the glamor and excess of American consumer society, with a focus on iconic American imagery. Additionally, American Pop Art tended to be more commercial and mass-produced, reflecting the consumerist nature of American society at the time. **

Both K-Pop and J-Pop have their own unique styles and appeal to different audiences. K-Pop is known for its catchy tunes, intricate choreography, and visually stunning music videos, while J-Pop often features a more diverse range of genres and tends to focus on emotional lyrics and melodies. Ultimately, the choice between K-Pop and J-Pop comes down to personal preference and what type of music and culture resonates more with each individual. **

Pop Art is a movement in art that emerged in the 1950s and 1960s, characterized by its use of popular culture imagery and themes. It often incorporates elements from mass media, advertising, and consumer products, blurring the lines between high and low art. Pop Art seeks to challenge traditional notions of art and elevate everyday objects and images to the status of fine art. It is known for its bold colors, graphic style, and playful approach to subject matter. **

A pop-up ad is a type of online advertisement that appears in a new browser window or tab, usually without the user's consent. These ads can be intrusive and disruptive to the user's browsing experience, as they often cover the content of the webpage they are visiting. Pop-up ads are commonly used to promote products, services, or websites, but they are generally considered to be annoying by internet users. **

A pop-up virus is a type of malware that generates unwanted pop-up advertisements on a user's computer or mobile device. These pop-ups can be intrusive and disruptive, often appearing without the user's consent and sometimes even when the user is not actively browsing the internet. Pop-up viruses can also be used to deliver other forms of malware or to trick users into clicking on malicious links. It is important to have up-to-date antivirus software and to be cautious when clicking on pop-up ads to avoid falling victim to a pop-up virus. **