WARNING: The following contains spoilers for Wolverine #5, by Benjamin Percy, Viktor Bogdanovic, Matthew Wilson and VC's Cory Petit, on sale now.
Marvel's latest event, X of Swords will be consuming the entire line of X-books over the next month. Its first issue revealed that the mutants of Krakoa will be participating in a sword fighting tournament over the rights to Krakoa/Arakko. Of the ten swords the mutants need to participate in the tournament, one of them is the Muramasa blade wielded by Wolverine.
Since the original Muramasa blade was melted down and formed into bullets by the Orphans of X in Tom Taylor and Juan Cabal's All-New Wolverine #28, Logan sets out on a journey to find Muramasa and have him forge a new blade. While the journey literally takes Logan through hell, it also reunites him with one of his most famous love interests.
Logan begins his journey by heading to Japan, the home of Muramasa and a country in which Wolverine has a long history. While there he meets old friends and foes, who offer clues to the whereabouts of the infamous swordsmith. Although Wolverine eventually discovers Muramasa is in the depths of hell, he pays a visit to his one-time bride to be, Mariko Yashida. The next few panels show Logan and Mariko enjoying each others company, and ends on Logan noting that old wounds don't matter much anymore, seemingly when put into perspective of his current battles, directly contrasting a statement he made in an earlier issue that he didn't believe in Krakoa
Old wounds are exactly what the relationship between Mariko and Wolverine has left, as the one time couple to be went through some traumatic events. Logan and Mariko first met in Mariko's debut issue, Chris Claremont and John Byrne's X-Men #118, which saw them instantly bond due to Logan's fluency in Japanese and deep knowledge of the country's culture and history. This bond was put into jeopardy as Mariko was bound to wed her father's criminal associate Noburu Hideki, which was chronicled in Wolverine's first solo series, Chris Claremont and Frank Miller's Wolverine (1982), which was the inspiration for the 2013 film The Wolverine.
After Wolverine successfully stopped Mariko from wedding Noburu he and Mariko became engaged. Unfortunately, Mariko was mind-controlled into calling off their wedding and strengthening the criminal ties of Clan Yashida. After breaking the mind control Mariko felt shameful for her actions and felt she could not wed Wolverine until she broke the clan's criminal connections.
Mariko became a large figure in the Japanese underworld but was eventually poisoned and died, sending her to hell for her connections to the underworld, and was forced to torture Wolverine's soul when he was sent to hell. Eventually she was reborn, leading to where Logan finds her in the issue, which somewhat mimics their journey together as Wolverine is once again sent to hell in order to retrieve the Muramasa blade.