This is an obscure title, a Korean karaoke game that requires not only an NTSC-J console but a compatible USB microphone as well. This game requires quite a lot of time invested and luck involved, with a number of achievements being glitchy. Good luck!
There is a way to totally idle this game, but it requires a few tools. In order to play the game at all you'll need a USB microphone (a cheap Logitech mic works fine), but in order to idle it you'll also need a fan, a turbo controller and a Vision Cam. Keep the vision cam plugged in, 
turboed on the controller, and 
rubberbanded. This will allow you to leave the game alone. Here is what each component does:
The USB mic will be plugged in. These cheap mics don't respond to frequency or pitch, they only respond to sound pressure. That means if you have something with consistent air pressure blowing into the microphone such as a fan or air conditioner, it will typically register most of the lyrics without much complication. Try to put the mic as close to the fan as possible to maximize the strength of the air velocity against the diaphragm of the mic.
With and constantly going on the turbo controller, this will allow you to pass from song to song without doing anything manually as well as selecting a new setlist of songs without touching the controller. If you want to change characters or select specific songs, I'd recommend turning off the turbo and removing the rubberband until you're set up the way you want it to be. It will also authorize the vision cam to take a picture if you level up.
The vision camera is used the most infrequently, as the game only prompts you to take a picture when you level up a character. With going on the turbo, you will agree to take a picture and have a snapshot taken of whatever the camera is pointing at. With that done, you'll just progress to the next setlist. If you use all of these tools, you'll never have to touch the game when leveling up. Adjust your play style accordingly based on what you do or don't have.
Now for the biggest tip:
NEVER QUIT OUT!!!!!!
Quitting out of a gig at any point is very likely to glitch the Old Man achievement on you, and it could never well take upwards of 5 more attempts, deleting your save and unlocking him again, or playing offline on another Xbox to unlock. The achievement is horrendously glitchy, so don't tempt it any more by quitting. If you need o turn your Xbox off in the middle of a gig, turn the fan off and fail out before backing out to the main menu and turning off your console. You have been warned!
So start off by setting up your tools and equipment. When selecting songs, you'll want to check out the whole setlist available to find a song called "Butterfly", a children's lullaby. The title will be displayed similar to the below video:
나비야 - (동요)
Difference is that the first part of the video title (2 characters) will be listed in parenthesis after the song name in the game. It might take a while for it to come up, or it might be the first time you load the game. Either way, the song is only about a minute and a half long without any really tricky phrases. Some people said they were able to just keep the mic by the fan and every phrase came out as "Great!". I didn't have it that easy, I had to keep the fan on the mic as I sat beside it, metal screaming into the mic for every phrase in order to provide additional sound pressure and push the bar further up from "Cool" to "Great!". Once you figure out what tactic works best for you and you get all "Great!" ratings in a song, you'll unlock:
게임 판정 도전슈퍼스타 모드에서 한 번이라도 게임을 Great 판정으로 모두 마쳐야 합니다.
You'll want to be playing as the boy character, Aadaru. Keep the fan on and choose songs that you seem to consistently score well on. If you score an S ranking on the first 3 songs you choose for a set, you'll unlock:
Note: This one can be buggy. I've gotten 6 S rankings in a set and it still didn't unlock. Just keep doing it until it decides to play nice.
Keeping with that theme, at the end of the song you'll see a "Music Score" alongside your ranking. Getting 97-100 on all 6 songs while playing will unlock the young man character as well as:
Keep playing as Aadaru until you reach 60,000 XP with him, bringing you up to level 2 and unlocking:
After hitting level 2 with him, switch to the little girl. You'll just need to keep your strategy going with her, as your only goal is to reach 240,000 XP. After you hit 130,000 you will unlock:
데뷰 졸업하기아라렐 캐릭터를 이용하여 데뷰 랭크를 클리어 합니다.
Note: This one is also prone to glitching. If you reach level 3 with her but don't unlock the achievement, play a few gigs as another character to level them up. That is likely to unlock this for you.
The remaining 90,000 will be so you can unlock the Old Man. Keep up your singing until hitting level 4 and unlocking the Old Man character. Before jumping into that, play as Tiara (the woman with a crown on her head). Your goal with her is only to get a Music Score of 100 on 3 consecutive songs, so choose songs you know you've scored 100 on before and hope for the best. Getting that done with her will unlock:
With that done, finish out the gig as Tiara. Now, the only character you haven't used is the young man with glasses. Choose him and do a gig, since you need to complete at least one gig with each character.
Now choose the Old Man and play through the gig normally as him. Wait until the point where there's a microphone in the background and the numbers descend rapidly. Some people speculate you need to have one of these numbers land on a 5, but this hasn't been confirmed nor denied. Try for it anyway! Play through the next song normally and wait for the spinner to come up. This is the trickiest part of the game. The green highlight and "Item" has to be on the #5. Once it is, you have to spin correctly and land on the #5. The technique I used to land on 5 consists of watching the bottom-center of the screen, right where 4 starts. You should see the solid outline of the arrow pass by here as it spins. On the exact very second you see that arrow come into view in that area, hit . This should make the arrow land on 5. I suggest practicing this technique throughout the entire game, making it second nature when it comes time to actually hit it. If you get it, play through the next song in the gig and hopefully unlock:
나바람의 운나바람 캐릭터로 파이널 선곡 시 아이템이 있는 5번째 곡을 선곡해야 합니다.
Note: This is the glitchiest achievement I've ever had the displeasure of fiddling with on Xbox. Quitting out definitely voids it, and the fixes are all time-consuming. You'll have to delete your save, re-unlock the Old Man, and fulfill the requirements again. You may have to play offline on a different Xbox in order to get it to unlock. I eventually got it after my 3rd save deletion and re-do. If it does glitch on you, I'd recommend proceeding on with the 2 Dog achievements before deleting your save. Incredibly annoying.
Regardless of whether or not you got the spinner in the correct area, hit it correctly, or unlocked the achievement you'll earn:
With the Dog unlocked, the real grind to 720,000 XP begins. Play up until you unlock the 5th and final gig from the list. You have to complete the entirety of the gig (6 songs) 10 times in a row without failing or quitting. Clear out some time for this one, as it takes 4 hours or so to get through. After the 10th gig, you'll unlock:
With that out of the way, earn your remaining 100,000 or so XP with the Dog to bring him up to the final level. Once you do, you should unlock:
Note: This one is glitchy as well. Go back and play another gig as your lowest level character, as getting them up another level should pop this one.
If you now need to re-start the Old Man grind, knock yourself out. While this game is mostly an idle with a fan and a turbo, it can still be more painful than crabs pinching your genitals. Best of luck and may your runs remain free of glitches!