Rare to find a game that permanently softlocks itself, especially as quickly and easily as this. The short version is if you insist on playing this game, do not assign the flight attendant "69" to manage any route but mars until you are entirely sure it is safe to do so.
The way the game works (at least in the part I was able to access) is that you send space ships back and forth along routes to earn money, which you can use to upgrade the ship/route to earn more money. You get one route to start, click a button to manually send it back and forth and/or level it up a few times until you have enough money to assign a flight attendant on your roster to manage it. Each flight attendant has one or more traits, and each route has a required trait and bonus traits. A flight attendant can only be assigned to manage a route if they have the required trait, and will generate bonus income if they have any of the bonus traits. The different flight attendants are acquired primarily through a gacha system, but a few are given to you as you progress the tutorial as well. Once you assign an attendant to manage a route, you can add another route, with the maximum you can have I believe being controlled by your CEO/Business Level (two terms the game seems to use interchangeably). This level is raised either by completing a set of quests or getting the combined level of your routes above a certain threshold. Once you complete either requirement, you can press a button to perform a prestige reset, increasing your CEO Level in exchange for losing all your existing ships/routes. The game is very explicit about the fact that this reset is the only way that you can change what route a flight attendant is assigned to, noting that you can lose out on mission rewards permanently by assigning flight attendants to the wrong routes. This is questionable design at best, but the real issue comes when combined with a tutorial that won't let you level up until you do what it wants.
The game has a mobile-standard heavily railroaded tutorial section, locking off your ability to do things until you follow step-by step instructions. As you progress through the tutorial, the game shows you that each route can only be run by certain flight attendants and that you currently do not have any flight attendants that can manage the Mars route. It also seems to indicate that you are unable to add a route if you don't have at least one flight attendant available who can manage it (I may have misunderstood but it is impossible for me to go back and check). The game then gives you the flight attendant 69, who has "Political Conformity 1" the trait required to manage the Mars route, and guides you to then add the mars route and assign her to manage it. Shortly after that you increase your CEO Level and, when assigning a flight attendant to manage the Luna route, 69 is available and marked as having a bonus when assigned to that route thanks to that same trait. The game allowed her to be assigned there and proceeded normally. Then, when selecting a third route, I decided to see if I was able to get mars, and found that I was able to. This might be because I had acquired another flight attendant, Madlenka, with the trait required to manage the Mars route. I do not know if that character is always acquired by this point or not. However, on attempting to assign a flight attendant to manage that route, I found that while the game listed both Madlenka and 69, neither were able to be selected. Rather than showing a price to assign either, 69 was marked as "Hired" Madlenka was marked as "CEO level 7 required for hire". Attempting to click either did nothing. It seems that in this situation it is impossible to assign a flight attendant to Mars. This is a problem, because everything that the game wants me to do requires a flight attendant to be assigned to Mars. The tutorial has just given me the flight attendant Urna, who is able to manage the route for Xepturia. However, I'm not allowed to add the Xepturia route until I hire a flight attendant for the Mars route. I cannot complete the quests either to get their rewards or to increase my CEO level, because one quest is to increase the level of the Xepturia route to 52 and the other is to send a message to Urna. The former cannot be completed without the Xepturia route added, and the latter cannot be completed because you can only send messages to flight attendants assigned to a route. I thought I might be able to salvage the situation by skipping those quests and just slowly grinding my total route level up to the required number listed, that being 420. However, the progress bar froze about 3/4 of the way through, and even though my level is currently shown as 586/420, but the bar is not full and clicking that area does not allow me to increase my CEO level.
When you run into a situation where a game is softlocked like this, generally the best solution is to restart the game completely, right? Unfortunately, Sexy Space Airlines seems to have no way to do this. There's no reset option in the settings menu. Reports from other users in the Steam community discussions say that uninstalling and deleting all local save data has no effect. Because the game does not seem to use steam cloud saves, I assume a save tied to your steam account is stored on the game's server. The solution, then, is to either make a second steam account specifically to play an underbaked porn game, or to play on Nutaku, where the game is playable in web browser or android and the save is presumably tied to a Nutaku account and also cannot be fixed if you run into another softlock. Either way, the save file tied to the original steam account's progress remains softlocked.
It's worth noting that there's some possibility there is a way out of this situation. While there is currently no way to progress, checking Mars' info panel shows two other portraits in a section labeled "Flight attendants with required traits". Hovering over them or clicking them doesn't provide any more info, but those portraits also appeared in the "Chance to contain" section of the "Character Luggage" that can be purchased from the shop for 10 units of premium currency. However, purchasing as many as I could with the currency the game had given me didn't give me any cards for either of them. Each character luggage contains 1-3 cards, and you need 5 copies of a character's card to unlock them. The game also says in a help section that at least some characters' cards can be acquired through "lost luggage" which is dropped slowly on a set timer for each route you are running, with an additional 10 being able to be acquired each day by playing minigames. The game states that Ada's card can be found in lost luggage acquired from Venus. Unfortunately, I've not gotten any cards out of luggage in my time attempting to find a way out of this situation, and don't know if either of the two characters I need can even have their cards drop from Mars, Luna, or Ganymede routes. It's also possible that the game slowly dripfeeds more premium currency. There is then a nonzero chance that normal gameplay could eventually result in acquiring one of those other flight attendants. There is no guarantee with the knowledge I have, however. As terrible of a choice as it would be to spend money on a game so poorly designed, I acknowledge that spending enough money on premium currency to buy more Character Luggage would presumably eventually unlock one of those characters. However, even then there's no guarantee that they aren't locked the same way that Madlenka is. It may or may not be a true softlock, but considering the observed droprates of cards combined with the difficulty and uncertainty of getting what I need, the time and/or money that I would need to invest to find out if it's a true softlock or not is significant enough that I am comfortable saying that there is no practical way to progress from this game state.
