Complex sentence: Vax Holser was the second most senior midshipman aboard UNS "Hibernia" after Seafort, junior to him by only six months, and initially resented this, leading to a serious fight between the two of them over control of the Midshipmen's wardroom.
Split into simpler sentences: Vax Holser was the next most senior midshipman aboard UNS "Hibernia" after Seafort, junior to him by only six months. He initially resented this, leading to a fight between the two of them over control of the Midshipmen's wardroom.