Arina

Arina didn't deliberately conceal or avoid her identity as a member of Night Chains from the Conductor. According to her, circumstances led her to join the organization after her mother's passing, and then she began traveling to various cities, living life on the go without a permanent residence. Night Chains allowed their members to have personal freedom outside of work, so this could somewhat explain the phenomenon of her "showing up everywhere."
When combat is necessary, Arina can cooperate with her phantoms and unleash astonishing combat power. The phantoms' state seems to be influenced by her mood. In a tranquil bar, they are merely regular servers, whereas on the battlefield, when Arina goes all out for the sake of earning the Conductor's praise, the phantoms' power will multiply as well.
As for what her goal outside of work and combat is, Arina's conduct has already made the answer clear as day. She will do anything to make the Conductor's gaze linger longer on her, all in the hope of being loved by the destined person.

Close interactions with Arina tend to make her seem mildly intimidating to others, but to the majority of those who do not know her on a personal level, she is a piteous woman in their view. Her faintly scarred body, lovely makeup, and meticulously coordinated outfit never fail to attract concern and offers of assistance from all sorts of people, but she always politely declines their kindness with the excuse that she's waiting for her lover to show up.
With her level of popularity, Arina was totally capable of getting a decently paid receptionist job in the bars and restaurants she used to work at or even working full-time for Night Chains to make higher bounties. Yet, despite receiving numerous recognitions and invitations from everywhere, she didn't do so and instead continued living life on the move. Once again, her excuse was that she was waiting for her lover to show up.
Fortunately, even a never-ending wait would conclude someday. The instant that person walked into the rest area, almost in a flash, Arina sensed something change within her and believed that was when she fell in love. Thereafter, to pursue this destined one, she used her own abilities to appear wherever the Conductor would be like a shadow and patiently made the Conductor drinks, hoping for her feelings to be accepted. If the Conductor didn't notice anything, she would intensify her ardor the next time until she deemed that her feelings had been made known.

For Arina, the more she loves and pines for someone, the more intense the burning becomes in her heart. Even if her lover is physically within reach, she will have to incessantly verify if their love or existence is actually real. It is a dealbreaker if her lover acts affectionately with anyone other than her, and she will demand them to spend multifold the time they spent with others to accompany her. Regardless of what she does, she wants her lover's opinion. Even when it comes to food or drink preferences, she has to repeatedly make sure it suits their palate.
Such excessively possessive concern is more likely than not unbearable for most people and might even frustrate them to the point of flaring up at her. Yet, Arina treats verbal and physical abuse as a reward, so violence is a completely futile option for resolving a conflict with her. The only solution she has to offer is, "If you don't love me and need me anymore, just kill me."
Needless to say, all her lover can do is refuse such a request. This will make Arina feel guilty for making an unreasonable demand, and rather than resent them for not killing her, she will yearn for more of their love.
"The above is the detailed analysis of Arina's relationship perspective! I suggest you think twice if you're considering to date her, Conductor!"