There are multiple characters your Shepard can choose to create a relationship with in the Mass Effect Legendary Edition. In the first game, Mass Effect 1, there’s a much smaller pool for you to pick from, but these characters carry over into the second game, and most of them continue to prosper in the third.
Male romance options
Ashley Williams is the human female you rescue on Eden Prime at the beginning of the game. You’ll have the opportunity to romance her after the end of any of the main missions in the game. You want to speak with her following the events of Feros, Noveria, and Therum when you rescue Liara. Each time you speak with her at this point, you’ll be able to build up the relationship, and you’ll want to choose the more positive options, which means picking the top option in the dialogue wheel, even if you’re playing as a Renegade Shepard.
On Virmire, there will be an option to choose between Ashley and Kaidan during the mission. If you choose to rescue Ashley, Kaidan will die, but you’ll have the chance to continue your romance with Ashley back on the ship, and you complete that romance by spending time together in your quarters before the final mission.
Female romance options
Kaidan Alenko is a human male that is working alongside you from the start of Eden Prime. He’s a member of the Normandy crew and remains with you throughout the rest of the game. Similar to Ashley, you can choose to speak with him following the end of any of the primary missions that take place on Feros, Noveria, and Therum. You will want to make sure to visit him on your ship each time to build the foundation for the relationship.
When the Virmire mission happens, you have the option to choose between saving Kaidan or Ashley. If you are attempting a relationship with Kaidan, you will want to make sure to save him during this mission. You can conclude this relationship by speaking to him on the ship after the mission, sharing an intimate moment with him on the Normandy during the lockdown, and you will share a private moment with him right before the final mission.
Male and Female romance options
Liara is an option for both the male and female versions of Shepard. You can start this romance much like Ashley where you’ll speak with her following the conclusion of any primary mission on Feros, Noveria, or Therum. You can choose to speak with her at any time between these missions, but you miss opportunities to build it up if you never speak to them, and you jump from all of the primary assignments.
Liara is probably the easiest romance option in Mass Effect 1. You’ll be able to build it up whenever Shepard has used a beacon in the game and has to connect with Liara. These comments will be on the top section and are considered the ‘paragon’ options whenever you share the visions with Liara. You’ll want to make sure to return to her in quarters in the Lab and Storage location of the ship.
If Shepard is attempting to create a relationship with Kaidan or Ashley while also having one with Liara, the pair will confront Shepard and force them to choose. The player will have to pick between the two. Shepard can suggest all three remain in a relationship, but Kaidan or Ashley will refuse. However, Liara chooses to stay in a relationship with Shepard, following this suggestion.